Curtis was abducted in Antakya, Turkey, in October 2012 where he planned to enter Syria

Curtis was abducted in Antakya, Turkey, in October 2012 where he planned to enter Syria

She also mourned the death of James Foley, whose parents have become her friends

She also mourned the death of James Foley, whose parents have become her friends

His mother Nancy Curtis thanks all those who helped to secure her son's safe release

His mother Nancy Curtis thanks all those who helped to secure her son's safe release

His release comes just days after another U.S. reporter, James Foley, was beheaded by the Islamic State group

His release comes just days after another U.S. reporter, James Foley, was beheaded by the Islamic State group

The mother of an American journalist who was released Sunday after two years in captivity said she is 'so relieved' to have her son on his way home, though she mourned the brutal killing of his fellow reporter James Foley.

Peter Theo Curtis was handed over to UN representatives, just days after Foley was beheaded by ISIS. Curtis is now safely outside Syria, U.S. government officials confirmed.

The United Nations said it helped with the handover to U.N. peacekeepers in a village in the Israeli-annexed Golan Heights and that Curtis was released to American authorities after a medical checkup.

'My heart is full at the extraordinary, dedicated, incredible people, too many to name individually, who have become my friends and have tirelessly helped us over these many months,' said Nancy Curtis.

'Please know that we will be eternally grateful.'

Curtis, 45, was abducted in Antakya, Turkey, in October 2012 from where he planned to enter Syria to teach English, according to Al Jazeera. He was held by the Nusra Front, the Qaeda affiliate in Syria, which has broken with the more radical ISIS.

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Free: Peter Theo Curtis, pictured, was handed over to UN representatives on Sunday, just days after another U.S. reporter, James Foley, was beheaded by the Islamic State group.

'We are so relieved that Theo is healthy and safe and that he is finally headed home after his ordeal, but we are also deeply saddened by the terrible, unjustified killing last week of his fellow journalist, Jim Foley, at the hands of the Islamic State in Iraq and Syria, ISIS,' Mrs Curtis said.

She said in the statement that she had gotten to know the Foley family over the months their sons had been captive.

'I have seen Diane Foley's bravery and her heroic efforts firsthand, efforts that helped rally the spirits of the families of all the journalists and others being held captive,' she said.

'We appeal to the captors of the remaining hostages to release them in the same humanitarian spirit that prompted Theo's release.

The release came on the same day as a memorial for Foley was held in New Hampshire.

U.S. officials declined to discuss details of the negotiations for the release of Curtis. It was not known what prompted Curtis' release, though his mother insisted no money changed hands, as some have speculated.

'While the family is not privy to the exact terms that were negotiated, we were repeatedly told by representatives of the Qatari government that they were mediating for Theo's release on a humanitarian basis without the payment of money,' she said.

'My entire focus right now is on helping the other families of those still being held in Syria, and on taking care of my son.'

Footage released on June 30 shows a relatively healthy-looking albeit disheveled Curtis, who also goes by the name Theo Padnos.

In the video obtained by Al Jazeera, Curtis read from a prepared script stating his name and profession, saying he was a journalist from Boston, Massachusetts.

He said he had been well treated and 'had everything' he needed.

'Everything has been perfect, food, clothing, even friends now,' he said on the tape, according to the broadcaster.

That account sits in stark contrast to the one told by his cellmate during some of his time in captivity.

According to the New York Times, American photojournalist Matthew Schrier, who escaped in July 2013 after being held for seven months, described being tortured and starved by his masked captors.

So desperate, Schrier eventually managed to crawl out of a hole in the wall he created by standing on Curtis' back and unraveling wires in a small opening.

Safe now: Curtis, pictured prior to his kidnapping, is safely outside of Syria now with a UN representative

Missing: Curtis reportedly went missing in Antakya, Turkey, as he was traveling to Syria in 2012

However, the heavier-set Curtis became stuck and chose to return to the cell where he remained for another 13 months. The pair were held in the rebel-held portion of Aleppo.

U.S. officials declined to discuss details of the negotiations for the release of Curtis. It was not known what prompted Curtis' release.

A cousin of Curtis', Viva Hardigg, declined to provide details on the circumstances of his release, but said he seems to be in good health.

Hardigg told The Associated Press: 'We are deeply relieved and grateful for his return and the many people who have helped us secure his freedom. At the same time, we are thinking constantly of the other hostages who are still held and those working to help them be freed. We want to do everything we can to support their efforts.'

Secretary of State John Kerry dubbed Curtis' safe release a victory for the U.S. and the journalist's family.

In a statement Sunday, he said: 'Particularly after a week marked by unspeakable tragedy, we are all relieved and grateful knowing that Theo Curtis is coming home after so much time held in the clutches of Jabhat Al-Nusrah.

'For two years, this young American has been separated from his family. Finally he is returning home. Theo's mother, whom we've known from Massachusetts and with whom we've worked during this horrific period, simply refused to give up and has worked indefatigably to keep hope alive that this day could be a reality.

Cellmates: Curtis, left, was held in a cell with American photojournalist Michael Schrier, right, who escaped in 2013

Before: Curtis was originally from Boston but had lived abroad for many years researching the Muslim faith

Author: Curtis, right,who also goes by the name Theo Padnos, wrote numerous books about Islam

'Over these last two years, the United States reached out to more than two dozen countries asking for urgent help from anyone who might have tools, influence, or leverage to help secure Theo's release and the release of any Americans held hostage in Syria.

'Every waking hour, our thoughts and our faith remain with the Americans still held hostage and with their families, and we continue to use every diplomatic, intelligence, and military tool at our disposal to find them and bring our fellow citizens home.'

National Security Adviser Susan E. Rice said in a statement that Curtis is now safe outside Syria and soon will be reunited with his family.

'For two years, we have kept Peter Theo Curtis, a U.S. citizen held hostage in Syria, in our thoughts and prayers. Today, we join his family and loved ones in welcoming his freedom,' she said.

Rice said the government had not forgotten the other Americans still held. There are believed to be four.

'...We hold in our thoughts and prayers the Americans who remain in captivity in Syria,' she said.

'Notwithstanding today's welcome news, the events of the past week shocked the conscience of the world. As President Obama said, we have and will continue to use all of the tools at our disposal to see that the remaining American hostages are freed.'

James Foley was beheaded by Islamic State militants who released a video last week blaming his death on U.S. airstrikes against their fighters in Iraq.

Foley's captors had demanded $132.5 million from his parents and political concessions from Washington. Neither obliged, authorities say.

For al-Qaida and some other militant bands, ransoms paid to free kidnapped Europeans over the past decade have surpassed donations from private supporters as a source of funding, according to the United States and Britain.

The British government, like the U.S., adheres to a longstanding policy against paying ransoms to extremists.

A senior Obama administration official said last week the Islamic State had made a 'range of requests' from the U.S. for Foley's release, including changes in American policy and posture in the Mideast.

Mrs Curtis said her son went to Syria because he wanted to help the people there.

'Theo has a deep concern and regard for the people of Syria, which is why he returned during the war,' she said. 'He wanted to help others and to give meaning and to bear witness to their struggles.'

She added: 'I am very fortunate that I do not have to tell his whole story. He eventually will be able to do so himself.'

Curtis was born Peter Theophilus Eaton Padnos in Atlanta, Georgia, where his father, Michael Padnos, who is now a writer living in Paris, was working as a lawyer.

He graduated from Middlebury College in Vermont, has a Ph.D. in comparative literature from the University of Massachusetts and is fluent in French and Arabic, his family said.

He also speaks German and Russian. He first became interested in writing about disaffected youth while working as a teacher in the Vermont prison system, resulting in his first book, 'My Life Has Stood a Loaded Gun.'

According to the family statement, while working as a journalist in Yemen, Curtis became interested in the stories of the many disaffected young men from the West coming to study Islam and he eventually wrote about them in his book, 'Undercover Muslim,' published in the United Kingdom.

He changed his legal name to Peter Theo Curtis after publication of that book to make it easier to travel in the Arab world, although he continued to work as a journalist, writing under the name Theo Padnos.