NEW YORK -LRB- CNN -RRB- -- Investigators have raised the wreckage of the helicopter involved in Saturday 's deadly mid-air collision over the Hudson River , but they were still looking for the small plane involved in the crash , authorities said Sunday . Divers unload a body from their raft onto a police boat Sunday . Nine people are believed dead in the crash . New York police said they believed side-scan sonar pointed them to the wreckage of the Piper Saratoga PA-32 just north of where the helicopter went down , but Deborah Hersman , chairwoman of the National Transportation Safety Board , said swift current and low visibility were hindering divers . The search stopped as a storm approached Sunday evening and will resume Monday morning , police said . Nine people , including five Italian tourists , were aboard the two aircraft when they collided over the river shortly before noon Saturday . Seven bodies had been pulled out of the river by Sunday afternoon , Hersman said . Authorities believe none of the nine people aboard the two aircraft survived the crash . Neither aircraft was required to carry electronic `` black boxes '' that record cockpit voices and flight data on larger planes , but electronic navigational devices on board might retain some information that could help the probe , Hersman said . Investigators are trying to establish the facts of the crash but wo n't determine the probable cause for some time , Hersman said . See where the collision occurred '' `` We are looking at everything . Nothing has been ruled out at this point in time , '' she said . Most of the Eurocopter AS350 had been lifted out of the Hudson on Sunday and taken to a pier in Hoboken , New Jersey , across the river from Manhattan , for examination , Hersman said . The helicopter was taking the five Italians on a 12-minute sightseeing tour around New York and had taken off from a heliport in midtown Manhattan shortly before the crash , she said . Watch crews search for victims '' New York police identified the pilot of the helicopter as Jeremy Clark , 32 . He had worked for the operator , Liberty Helicopter Sightseeing Tours , for about a year and a half and had 2,700 helicopter flight hours , Hersman said . iReport.com : Were you there ? Send images His passengers were Michele Norelli , 51 ; Fabio Gallazzi , 49 ; Filippo Norelli , 16 ; Giacomo Gallazzi , 15 ; and Tiziana Pedroni , 44 , all of Bologna , Italy . The plane took off from a Philadelphia-area airfield Saturday morning , landed at New Jersey 's Teterboro Airport and was bound for Ocean City , New Jersey , with three people aboard -- the owner and pilot , Steven Altman , 60 , of Ambler , Pennsylvania ; his brother , Daniel Altman , 49 , of Dresher , Pennsylvania ; and Daniel Altman 's son Douglas , 16 . Controllers lost contact with the plane at 11:53 a.m. , when it was at an altitude of about 1,100 feet , Hersman said . View images from the scene '' Hersman said the NTSB has recorded eight accidents and one `` incident '' involving Liberty , but Saturday 's crash was the first to involve fatalities . Previous accidents included a 2007 case in which a helicopter crash-landed in the Hudson from a height of 500 feet , but without injuring passengers ; a 2008 incident in which one helicopter taking off clipped another on the ground ; a 2008 incident in which a pilot caused `` substantial damage '' to a helicopter while landing during an instructional session . In 2001 , a Liberty pilot made an `` improper decision '' to continue flying in poor weather at night , causing the helicopter to hit trees , according to the NTSB . Marcia Horowitz , a spokeswoman for the tour operator , said Liberty executives `` are cooperating fully '' with investigators . `` Right now , the company is focusing its efforts on cooperating with the NTSB and giving as much information as it can , '' Horowitz said . `` At this time , their priority is to help with the family of their pilot , and of course the families that were involved in the accident . '' Investigators will focus on radio communications along the congested air corridor at the time of the crash and examine any pictures or video contributed by the public , Hersman told CNN earlier . Witness accounts and still photographs already provided `` good information '' to investigators , she said . A witness told investigators he saw the airplane approach the helicopter from behind , and the plane 's right wing make `` contact with the helicopter , '' Hersman said . The witness , another Liberty pilot who was refueling at a nearby heliport , said he tried to warn the helicopter pilot but got no response . Other witnesses reported seeing debris flying from the helicopter as it slammed into the water . Arnold Stevens , who saw the collision from the W Hotel in Hoboken , said the helicopter `` dropped like a rock , '' while one of the plane 's wings was sheared off and it began `` corkscrewing '' into the water , he said . The busy airspace surrounding Manhattan has been the site of several recent aeronautical accidents . Earlier this year , a US Airways plane with 155 people on board ditched into the Hudson after apparently striking birds upon takeoff from New York 's LaGuardia Airport , officials said . Capt. Chesley B. `` Sully '' Sullenberger 's landing , which resulted in no deaths or serious injuries , was captured on closed circuit television . In 2006 , Yankees pitcher Cory Lidle , 34 , and his flight instructor were killed when the ballplayer 's plane crashed into a high-rise apartment building near the East River , city officials said . CNN 's Susan Candiotti contributed to this report .