Rebel militias deny holding British aid worker Hassan

Confusion surrounded the fate of the Iraq aid worker Margaret Hassan last night after main rebel groups denied being involved with her kidnap.

Insurgents in Fallujah condemned the abduction of the charity chief who was snatched by an armed gang in Baghdad six days ago. Despite making a video of the hostage in captivity, the kidnappers have not been pictured or made any claim of responsibility.

The statement by the Fallujah group came a day after the husband of Irish-born Mrs Hassan made an plea for her release on an Arabic TV station.

"This woman works for a humanitarian organisation. She should not have been kidnapped," the emir, or commander, of one group of Iraqi insurgents in Fallujah told Reuters reporters.

"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," he added.

Commanders of five separate guerrilla groups in Fallujah said they were not holding Mrs Hassan and had seen no evidence that Abu Musab al-Zarqawi's organisation had kidnapped her.

The US military and Iraqi government officials say Fallujah is a base for foreign militants loyal to Zarqawi, a Jordanian whose group has claimed responsibility for kidnappings and murders, including that of British hostage Ken Bigley.

Mrs Hassan, who worked in Iraq for the aid agency Care International and holds 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.

On Saturday, her husband Tahseen Ali Hassan begged for her to be freed "in the name of Islam", as he appeared on another station, al-Arabiya.

"It hurts to watch my wife cry," he said. "This scene has saddened and worried her friends and loved ones. I plead with you, in the name of Islam and Arabism - while we are in the most sacred Islamic month - that my wife and beloved return to me."

Charity Care International has also pleaded for Mrs Hassan to be freed in a statement read on al-Jazeera by the organisation's secretary general, Denis Caillaux.

He said she was dedicated to the Iraqi people and added: "She is a naturalised Iraqi citizen and always holds the people of Iraq in her heart."

Yesterday, the Foreign Office refused to be drawn on a Sunday newspaper report that British security officials were trying to find the intermediary who established contact with the captors of Ken Bigley during his kidnap ordeal.

It was claimed they want to ascertain if she is being held by the group which seized and eventually killed Mr Bigley.

The report also said Prime Minister Tony Blair and Foreign Secretary Jack Straw had been asked to take a back seat in appeals for her release with Care International taking the lead.

A Foreign Office spokesman would only reiterate that efforts were continuing on her behalf, saying: "We are working closely with the Iraqi authorities to secure Margaret's release."

Mrs Hassan, who was born in Dublin, appeared in a video shown on al-Jazeera on Friday.

She looked tired and distraught in the video as she called on Tony Blair to pull out of Iraq and not to send troops to Baghdad.