The camp, run by Islamic radicals who call themselves Ansar al-Islam, had been pummeled from the air for several days before US and Kurdish forces entered the compound, located in a Kurdish-controlled area near the border with Iran, according to General Richard Myers, chairman of the Joint Chiefs of Staff.

"We are in there on the ground with lots of force, with some Kurdish help," Myers said on CNN's "Late Edition" show.

An undisclosed number of camp defenders, described by Myers as likely al-Qaeda members, have been killed during the operation, while other have been captured.

"We're now in there on the ground and starting our investigation of exactly who's up there and what's up there," the general said.

"Some of the bodies that we have recovered, enemy bodies that have been recovered up there, are not Iraqis, they're not Iranians. We don't know for sure, but they're most likely al-Qaeda," he went on.

Myers said the camp was the one US Secretary of State Colin Powell mentioned in his much-publicized speech before the UN Security Council last month as proof of the Iraqi government's secret ties to the al-Qaeda network, blamed for the September 11, 2001 attacks on the United States.

Powell said an Iraqi intelligence agent had offered al-Qaeda a safe haven in the region, which some members of the group gladly accepted after the United Stated launched Operation "Enduring Freedom" in 2001 to topple the Taliban government in Afghanistan and drive bin Laden's forces out of that country.

According to US intelligence officials, the bin Laden followers, who operated in northern Iraq, created a secret biological weapons laboratory inside the camp that was used to produce ricin and other poisons.

There is concern the ricin discovered during a police raid on a London apartment last January may have been produced at this lab with the purpose of poisoning British troops, the officials have said.

"It's from this site where people were trained and where poisons were developed that migrated into Europe," Myers said.

The general said he was unaware of any discoveries of weapons of mass destruction in the camp, but added that the Ansar al-Islam compound was large and had a tunnel network underneath it that still needed to be explored.

"It may take us up to a week to exploit that, to investigate that site and determine what is there," he stressed.

He said the US military also had in its possession laptop computers and documents that might shed some light on the Iraqi weapons of mass destruction program.

"We're going to have to put these pieces together," said the chairman of the Joint Chiefs of Staff. "We have people that are working that.

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