By . Paul Bentley In Praia Da Luz . and Martin Robinson . and Kieran Corcoran . Police hunting for Madeleine McCann have today started searching Praia da Luz's sewer network as it emerged they need at least another week to scour land 300 metres from where she vanished. Scotland Yard detectives working in the Algarve resort have pulled up manhole covers and are analysing the network of pipes below using micro cameras and fibre-optic cables. Police have yet to say whether they have found anything significant, but Madeleine's parents - Kate and Gerry McCann - today said they were 'encouraged by the progress' of the search. Scroll down for video . New phase: Police also inspected sewers under wasteland minutes from where Madeleine was last seen . Manhole covers were lifted and cameras dropped down to survey the complex network of pipes . Discovery: The hole has been been subject to intense police investigation since it was discovered on Wednesday. It is believed to have been used by children playing in the area for years . The sewer system being searched was installed as part of failed plans . to build a hotel on the site before Madeleine disappeared in 2007, but after a planning battle it remained wasteland. The search of the area for clues to what happened to the three-year-old from Leicestershire is expected to go into a second week after British police were granted an extra seven days by the Portuguese authorities to keep searching. Sources said detectives had not realised just how hard and dry the land would be where they have been digging for clues. The extension may also have been granted after surprise finds at the first site, where a large concealed shaft was discovered by sniffer dogs. The hole has now been cleared after forensic teams removed ‘non organic’ materials from inside. Local reports suggested clothing had been found in what was a discarded play den for children. Officers also believed they had come . across a burial site late on Wednesday but this has since reportedly . been ruled out as an area of interest. Bones have been discovered on the . site but tests showed they were from cows and pigs. Scotland Yard has refused to provide . ‘a running commentary’ on whether any leads have so far been found. Experienced: Seven-year-old English springer spaniels 'Tito and Muzzy' from South Wales Police, who helped hunt for April Jones, were back on the land for a fourth day . Hot work: The dogs were covered in water and a wet blanket as their handlers ensure they did not overheat in the Algarve sun . However, Mr and Mrs McCann today wrote online to well-wishers saying they are 'encouraged by the progress'‎ of searches for their missing daughter. ‎Writing . on the couple's official Find Madeleine Facebook page, Kate and Gerry . McCann said: 'We are kept updated on the on-going work in Portugal and . are encouraged by the progress. 'Thank you for continuing to stand by us and supporting our efforts to get Madeleine home.'‎ . Mr . and Mrs McCann, who have not travelled to Praia da Luz, were previously . said to have been bracing themselves for 'significant news'. Today a group of officers lifted a manhole cover and lowered what appeared to be a camera attached to a long pole down it. One of them wrote notes as they looked inside, around 20ft (6metres) from where the radar equipment was used yesterday. They then moved over to a section of grass nearby and lifted another cover, with an officer lying on his front on the ground to reach inside. Meanwhile sniffer dogs used to hunt for murdered schoolgirl April Jones were again on the site hunting for evidence. The seven-year-old English springer spaniels – Tito and Muzzy – can cover a far larger area than humans in much less time. Yesterday they uncovered  concealed shaft covered with corrugated iron, yards from the spot where Madeleine McCann vanished. Scotland Yard moved in to seal off the area with large white tents. Forensic approach: Police have split the wasteland into at least 12 areas of interest, using dogs, scanning equipment and fingertip searches . Vantage point: At the centre of the search site is a hill, where officers on horses and also with telescopes are taking advantage of the height to look for evidence . Five forensic officers were called in to start excavating the shaft and were seen removing several bags of evidence. The shaft had an opening measuring around 5ft by 3ft which was . covered with wooden planks, a large corrugated iron sheet and mounds of . earth. A . local source said: ‘The discovery of the hole came as a surprise. Police are meant to be here for five to seven days but this may delay . things.’ The . area is the size of three football pitches and is thought to contain at . least 12 key areas of interest which officers are planning to examine. It was chosen because a suspect who was carrying a young girl was seen . walking in the direction of the site on the night that Madeleine was . last seen alive. Investigation: Madeleine’s parents Kate, 46, and 45-year-old Gerry McCann have not travelled to Portugal but are being kept closely informed and are said to expect 'significant news' on their daughter . Map: The search site is 300 metres from the apartment at the Ocean Club resort in Praia da Luz and the tapas bar her parents were dining at and close to where a suspect was seen with a girl in his arms on the night she was abducted in May 2007 .
Cameras searching pipework constructed for hotel that was never built .
Three manholes lifted on land 300 metres from where Madeleine vanished .
Gerry and Kate McCann posted online to say they are 'encouraged'
Madeleine's parents are not in Portugal, but are being kept closely updated .
Scotland Yard officers still digging holes and clearing land in Praia da Luz .
They have been granted an extra week by Portuguese authorities to dig .
Police sources say they did not realise how hard and dry the land would be .
Search concentrated on area where mystery man was seen carrying a child .
Used radar and diggers to examine plot in middle of search area .
By . Paul Bentley In Praia Da Luz . and Martin Robinson . and Kieran Corcoran . Police hunting for Madeleine McCann have today started searching Praia da Luz's sewer network as it emerged they need at least another week to scour land 300 metres from where she vanished. Scotland Yard detectives working in the Algarve resort have pulled up manhole covers and are analysing the network of pipes below using micro cameras and fibre-optic cables. Police have yet to say whether they have found anything significant, but Madeleine's parents - Kate and Gerry McCann - today said they were 'encouraged by the progress' of the search. Scroll down for video . New phase: Police also inspected sewers under wasteland minutes from where Madeleine was last seen . Manhole covers were lifted and cameras dropped down to survey the complex network of pipes . Discovery: The hole has been been subject to intense police investigation since it was discovered on Wednesday. It is believed to have been used by children playing in the area for years . The sewer system being searched was installed as part of failed plans . to build a hotel on the site before Madeleine disappeared in 2007, but after a planning battle it remained wasteland. The search of the area for clues to what happened to the three-year-old from Leicestershire is expected to go into a second week after British police were granted an extra seven days by the Portuguese authorities to keep searching. Sources said detectives had not realised just how hard and dry the land would be where they have been digging for clues. The extension may also have been granted after surprise finds at the first site, where a large concealed shaft was discovered by sniffer dogs. The hole has now been cleared after forensic teams removed ‘non organic’ materials from inside. Local reports suggested clothing had been found in what was a discarded play den for children. Officers also believed they had come . across a burial site late on Wednesday but this has since reportedly . been ruled out as an area of interest. Bones have been discovered on the . site but tests showed they were from cows and pigs. Scotland Yard has refused to provide . ‘a running commentary’ on whether any leads have so far been found. Experienced: Seven-year-old English springer spaniels 'Tito and Muzzy' from South Wales Police, who helped hunt for April Jones, were back on the land for a fourth day . Hot work: The dogs were covered in water and a wet blanket as their handlers ensure they did not overheat in the Algarve sun . However, Mr and Mrs McCann today wrote online to well-wishers saying they are 'encouraged by the progress'‎ of searches for their missing daughter. ‎Writing . on the couple's official Find Madeleine Facebook page, Kate and Gerry . McCann said: 'We are kept updated on the on-going work in Portugal and . are encouraged by the progress. 'Thank you for continuing to stand by us and supporting our efforts to get Madeleine home.'‎ . Mr . and Mrs McCann, who have not travelled to Praia da Luz, were previously . said to have been bracing themselves for 'significant news'. Today a group of officers lifted a manhole cover and lowered what appeared to be a camera attached to a long pole down it. One of them wrote notes as they looked inside, around 20ft (6metres) from where the radar equipment was used yesterday. They then moved over to a section of grass nearby and lifted another cover, with an officer lying on his front on the ground to reach inside. Meanwhile sniffer dogs used to hunt for murdered schoolgirl April Jones were again on the site hunting for evidence. The seven-year-old English springer spaniels – Tito and Muzzy – can cover a far larger area than humans in much less time. Yesterday they uncovered  concealed shaft covered with corrugated iron, yards from the spot where Madeleine McCann vanished. Scotland Yard moved in to seal off the area with large white tents. Forensic approach: Police have split the wasteland into at least 12 areas of interest, using dogs, scanning equipment and fingertip searches . Vantage point: At the centre of the search site is a hill, where officers on horses and also with telescopes are taking advantage of the height to look for evidence . Five forensic officers were called in to start excavating the shaft and were seen removing several bags of evidence. The shaft had an opening measuring around 5ft by 3ft which was . covered with wooden planks, a large corrugated iron sheet and mounds of . earth. A . local source said: ‘The discovery of the hole came as a surprise. Police are meant to be here for five to seven days but this may delay . things.’ The . area is the size of three football pitches and is thought to contain at . least 12 key areas of interest which officers are planning to examine. It was chosen because a suspect who was carrying a young girl was seen . walking in the direction of the site on the night that Madeleine was . last seen alive. Investigation: Madeleine’s parents Kate, 46, and 45-year-old Gerry McCann have not travelled to Portugal but are being kept closely informed and are said to expect 'significant news' on their daughter . Map: The search site is 300 metres from the apartment at the Ocean Club resort in Praia da Luz and the tapas bar her parents were dining at and close to where a suspect was seen with a girl in his arms on the night she was abducted in May 2007 .
metres from where she vanished. Scotland Yard fibre-optic cables. Police have yet to say Madeleine's parents - Kate and Gerry McCann - minutes from where Madeleine was last seen . wasteland. The search of the area for clues to week after British police were granted an extra seven days by the Portuguese authorities to keep realised just how hard and dry the land would be where they have been digging for clues. The they are 'encouraged by the progress'‎ of updated on the on-going work in Portugal and . McCann, who have not travelled to Praia da Luz, suspect who was carrying a young girl was seen . that Madeleine was . last seen alive. Portugal but are being kept closely informed and