Insurgent commanders in the Iraqi city of Fallujah have said they are not holding foreign hostage Margaret Hassan and have condemned her kidnapping.
"This woman works for a humanitarian organisation. She should not have been kidnapped," said the emir, or commander, of one group of Iraqi insurgents in the town.
Many of the scores of kidnappings in Iraq since April have taken place around Falluja, a fiercely anti-American guerrilla stronghold 50 km west of Baghdad.
The US military and Iraqi government officials claim Fallujah is a base for foreign militants loyal to declared al Qaeda ally Abu Musab al-Zarqawi, a Jordanian whose group has claimed responsibility for kidnappings and suicide bombings.
Commanders of five separate guerrilla groups interviewed in Falluja said they were not holding Hassan and had seen no evidence that Zarqawi's organisation had kidnapped her.
Zarqawi's Tawhid wal Jihad (One God and Holy War) group claimed responsibility for the kidnapping and beheading of two Americans and a Briton seized in Baghdad last month.
Hassan , who holds Irish, British and Iraqi citizenship, was seized on Tuesday. She appeared on a video on Arabic Al Jazeera television on Friday making a tearful plea for her life.
There is no indication of which group is holding Mrs Hassan.
One guerrilla commander in Falluja said he believed Hassan may have been the victim of a criminal kidnapping.
"She had been living in Iraq for 30 years and she was a humanitarian. The resistance did not kidnap her because this would have left a bad impression of the resistance in the world," said the commander, who asked not to be named.
Hassan was seized from her car on her way to work by gunmen said by her husband to have included one in police uniform.
She was the eighth foreign woman to have been kidnapped in Iraq in the last six months. The others, including two Italian aid workers held for three weeks in September, have been freed.
A Falluja guerrilla commander said he did not see a political motive for abducting Hassan , who had worked in Iraq for the aid agency Care International since the early 1990s.