One of two French journalists released from captivity in Iraq has said he saw other hostages who were later beheaded.
Georges Malbrunot was held for 124 days
Georges Malbrunot, giving details of his ordeal in the French media, said he and his colleague Christian Chesnot both feared for their lives at times.
Mr Malbrunot said his captors were driven more by Islamic holy war than Iraqi nationalism.
"One of the lessons we drew from our captivity was that we were immersed in Planet Bin Laden," he said.
When the men were freed earlier this week, their captors said it was because of France's anti-war stance.
But Mr Malbrunot told French television the influence of the al-Qaeda leader was especially strong while they were with "a cell of the Islamic Army in the north".
"We were very aware of the fact that it wasn't the Iraqi agenda that motivated our kidnappers, but the internationalist jihadist agenda.
"I think this is the real challenge for the next 10 years - the clash of cultures that these people are advocating, are seeking."
Writing in the French newspaper Le Figaro, he said he had seen hostages who were later killed by their captors.
They included two Macedonians, an Iraqi power station executive and a bodyguard for Iraqi politician Ahmed Chalabi.
Mr Malbrunot warned other journalists working or thinking of working in Iraq to take care.
"Our kidnappers told us: Don't come back to Iraq, this is a land of war and we do not need you here. We want to settle our scores with the Americans.
"I would say you must be very, very careful because that country is crawling with armed men who are on the lookout for Westerners."
He said that, at times, both he and Mr Chesnot feared they would be killed.
In a separate interview on RTL radio, Mr Malbrunot said it would take time to recover from the ordeal.
"But the life of a free man is far easier than that of a hostage," he said.
Mr Chesnot, 37, and Mr Malbrunot, 41, were abducted in August while driving to the city of Najaf with their Syrian driver, Mohammed al-Jundi, who was later found during the US-led assault on Falluja.
The pair arrived at the Villacoublay military airbase near Paris on Wednesday where they were met by family members, President Jacques Chirac, and the French prime minister and defence minister.
French officials have denied that a ransom was paid and many in France are expected to take the view that the men's release vindicates the country's opposition to the war in Iraq.