'Brainwashed': Amer Deghayes was exploited by radical Islamists before he went to fight with jihadists in Syria, according to his mother . The mother of three teenagers who ran away to Syria to wage jihad says her sons were 'brainwashed' by YouTube videos and their extremist friends. Inas Abulsayen was left heartbroken when her sons left their home in Sussex and travelled to fight with a branch of Al Qaeda against the Assad regime. Her two younger sons Abdullah and Jaffar Deghayes have now been killed in the war-torn country, and she has launched a public appeal for their older brother Amer to come home. Amer, 20, left the family home in Saltdean, near Brighton, in October 2013 and joined the Al Nusra Front, and two months later his brothers joined him in Syria. In April last year, 18-year-old Abdullah was killed in a battle which also left Amer injured, and in October Jaffar died while fighting against Assad's troops in December. Despite his brothers' deaths, Amer is determined to remain in the Middle East, and has ignored his family's demands for him to return to Britain. Mrs Abulsayen said her sons were influenced by radical videos which they watched online, and insisted that she and her husband Abubaker were opposed to extremism. 'My sons went to serve, to sacrifice, and now two of them are dead,' she said. 'They were victims. They felt England was a part of their lives, but everybody has a secret life. 'We have our religion, but there is lots of brainwashing on YouTube, in the mosques, through friends. 'My sons are Muslim, and they believe everyone should be free as part of humanity. I taught them about the uprising, but not about fighting, maybe they thought they are men and maybe they were brainwashed.' Scroll down for video . Killed: Abdullah, left, and Jaffar, right, both died fighting in Syria for the Al Nusra Front, a branch of Al Qaeda . Home: The three brothers abandoned the family house in Saltdean, Sussex to fight in Syria . The mother of six said that her sons' friend Ibrahim Kamara, 19, influenced them with his radical views when he was staying with them after falling out with his own family. Mrs Abulsayen said: 'I had lots of arguments with him because he talked about Osama Bin Laden, jihad - and I didn't want my sons in this position. He had a bad view on Islam. 'I heard Ibrahim say to Jaffar, "You are not young now, Jaffar. You are old enough, you can look after yourself."' Kamara died in a US air strike in Aleppo last year after travelling to Syria with Jaffar. Mrs Abulsayen added that her sons told her they wanted to carry out humanitarian missions but instead turned to jihad once they arrived in Syria. 'Amer was the first one to leave in October 2013,' she said. 'He said to me, "Mummy, there is a community that has English people who want to help refugees. This is my chance. Let me make that trip. It's not that dangerous." 'He said to me, "Mummy, I feel guilty. I have food, I have everything here - don't be upset with me. This is the best opportunity for me. People are hungry and children are crying." 'He is very calm, like all my sons, and he gave me a promise he would be back. He said it was just a trip to help refugees. ''If I die, you will be upset if I am martyred', he said to me. I said of course - you know my opinion on going to Syria - I disagree with it.' Father: Abubaker Deghayes outside his home in October, announcing that Jaffar had been killed . Uncle: Omar Deghayes spent five years as a detainee in Guantanamo Bay before being released . Three months later, her two other sons left without telling their family where they were going, she said. 'Abdullah, the first one to die, I didn't even get to give him a hug before he left,' she continued. He didn't say goodbye to me. Abdullah left and gave his sister a hug before saying, "I'm going to meet my mate." 'Two weeks before he left, Jaffar told me he would never leave me, so I don't know who brainwashed him. Maybe he thought he could get his brothers back, I don't know.' The boys' uncle, Omar Deghayes, was a detainee at Guantanamo Bay for five years after being arrested in Pakistan, but was eventually released without charge. In a film shot last year, Amer insisted he would not return home, saying: 'My work here is not done. I came here to give victory to the people and make sure that they receive justice, and we still haven't reached the goal yet.' He added: 'The Muslim nation is like one body. If one part complains, the other parts react, so I don't see it as a Syrian conflict. I see it as an Islamic conflict.' If he did return to Britain, Amer could face legal action, because the Al Nusra Front is classified as a banned terrorist organisation by the Government.
Inas Abulsayen has seen her sons Amer, Abdullah and Jaffar Deghayes travel to Syria and join Al Nusra Front . Adbullah, 18, and Jaffar, 17, are now dead while Amer, 20, is still in Syria . Mother says her sons were brainwashed by YouTube and their friends . Pleads for Amer to return to their home in Sussex after brothers' deaths .