Friends described Peter Moore as easy going and hardworking
Peter Moore, one of five British men taken hostage in Iraq in May 2007, spent years working as a volunteer in both Guyana and China before he was kidnapped in Iraq.
The 36-year-old from Lincoln was working for American management consultancy Bearingpoint when he was seized at Baghdad's Ministry of Finance.
Four other men captured at the same time were contractors employed to guard him. At least three are known to have been killed.
According to one of his friends, Mr Moore - who had been volunteering in Guyana for three years before he went to Iraq - thought working as a consultant in Iraq presented "a good opportunity to earn money".
Koenraad Backers, 39, a business consultant from Holland, said he and Mr Moore both started working for Voluntary Service Overseas (VSO) in Guyana in 2004.
He said his "motor-cycle loving" friend was very sociable and easy-going, but also "incredibly hard working".
"He had done a lot of development work before - in China," he said.
In Guyana, Mr Moore started out teaching computer science at a teacher training college, before working as an IT consultant for the Lands and Survey department.
His last role was at the Guyana Geology and Mines Commission, but Mr Backers said his friend had fallen in love with the country.
"He really wanted to settle in Guyana but needed money to do so - which is why he went to Iraq. He planned to do consultancy work for about four to six months, but it was way more dangerous than he expected.
"When he got there, he wanted to get out. He witnessed bomb attacks, he was constrained to a small area, he didn't feel safe," he said.
Mr Backers said it was "great news" that his friend had been released, but his biggest worry was "his mental state".
"I understand he is in good shape, but we don't know how he was treated, we only have one video of when he was in captivity, and then he looked very different - he didn't look very good.
"I hope he can settle and enjoy being free again," he added.
Another of Mr Moore's friends from Guyana, Stuart May, said everyone in Guyana was "thrilled" he had been released.
"I was the one who dropped Pete off at the airport when he left Guyana and headed off to Iraq.
"When I heard the news I was very emotional because I can now look forward to completing the journey when I pick him up."
David Thomas, another friend, said the people of Guyana had a huge amount of respect for the volunteer.
"In Guyana they have a phrase 'big man' - it means great man. Peter was known as a 'big man'. He'd earned the respect of the country, for the hard work he had done," he said.
Kevin Pickett, an exploration geologist who also befriended Mr Moore in Guyana, echoed the sentiments, saying he was "over the moon".
The Labour MP for Lincoln, Gillian Merron, who knew Mr Moore personally, said his release was "outstanding news".