Abdel Hakim al-Hasady, a former Islamic fighter in Afghanistan, now recruits, trains and deploys 500 rebels fighting to topple Libya's Muammar Gaddafi.

He says he was once questioned for two months by U.S. agents in Pakistan for suspected ties to al Qaeda -- which he denies -- and was later imprisoned in Libya for three years.

The presence of Hasady and other Islamists among the rebels raises difficult questions for the United States and other Western powers, who want Gaddafi's overthrow but worry al Qaeda may establish a stronghold on the Mediterranean coast.

Gaddafi has accused al Qaeda of playing a direct role in Libya's unrest in a plot to destabilise the oil-producing, North African Arab country and set up a regional base.

He has labelled several insurgency leaders, including Hasady, as al Qaeda members or sympathisers.

Rebel leaders and fighters say they are inspired by popular revolutions in Egypt and Tunisia, not al Qaeda.

Sitting in a mosque compound in Darna, an eastern Libyan town seen as sympathetic to Islamists, Hasady, 45, said he never had ties to al Qaeda.

Wearing a green military camouflage uniform with a pistol tucked into his belt, he expressed concern that the United States and other Western countries may take Gaddafi's al Qaeda allegations seriously and hold back on providing the heavy weapons and helicopters he says they need.

"The West is hesitating because of their fears of al Qaeda in Libya. They must believe Gaddafi," said Hasady, 45.

Western states have demanded that Gaddafi quit office but some governments in the region are nervous that al Qaeda could step into a chaotic power vacuum if he does.

Neighbouring Algeria, which has fought Islamist insurgents for two decades and opposed the Western military intervention, says al Qaeda has acquired some arms in Libya, including surface-to-air missiles, and is smuggling them to northern Mali.

But there are few signs of Islamist militants on Libya's front line.

Hasady, an Islamic preacher and teacher who spent time at a training camp in Afghanistan, was arrested by Pakistani authorities after the U.S.-led invasion of Afghanistan in 2001 and then turned over to American agents in Islamabad, he said.

His story has changed several times in interviews, suggesting it will be difficult for Western countries to tell friend from foe as the Libyan conflict drags on and they try to formulate a strategy to stabilise the country.

Kamran Bokhari, regional director of global intelligence firm Stratfor, said the presence of people like Hasady "further compounds concerns that the collapse of the Gaddafi regime could descend Libya into the kind of chaos that al Qaeda and its allies see as a prerequisite for their objectives.

"There is no way to tell whether or not the likes of Hasady have abandoned their old ambitions and if so to what extent," he told Reuters.

"The Americans detained me in Pakistan and asked me if I belonged to al Qaeda. They asked me if I ever met Osama bin Laden. I told them no. Even if I had met bin Laden, does that make me al Qaeda? Journalists met him. Does that make them al Qaeda?"

Hasady said previously that he fought the Americans in Afghanistan. Now he says he only engaged in "self-defence" against U.S.-backed Afghans who fought the Taliban.

He demanded more muscular Western intervention in Libya.

"A no-fly zone is not enough. How can we defeat Gaddafi without heavy weapons from the West? All we have is some AK-47 rifles and a few rockets."

Although Islamists are not dominant in Libya's opposition, they are regarded as far more disciplined than other fighters.

Little is known in the West about Hasady and other Islamists.

Bokhari said the rebels are composed of a diverse array of ideological elements from secularists to Islamists to jihadists.

"What this means is that it is very difficult for the outside world to figure out who is who. This situation exacerbates the fears that Islamists and jihadists could exploit efforts to topple the Gaddafi state."

Hasady was released to Libyan custody after his detention in Pakistan. He was later imprisoned in Libya from 2004-2007 and then freed as part of a reconciliation with Islamists.

"I am a simple man. I am not al Qaeda. I am a Libyan Muslim," he said. "If the Americans don't want to help us, if the West doesn't want to help us, to hell with them."