US says bin Laden group has crude chemical weapons

The US says Osama bin Laden's al-Qaida may have crude chemical weapons, but lacks the hi-tech means to deliver them.

A senior US defence official said they would have to use primitive but "innovative" methods to attack people with them.

He named possibilities as crop-dusters and hand sprayers.

Among the weapons are chlorine and phosgene poison gases - used as weapons in the First World War.

The official says believes Al Qaida does not have any more complex chemical weapons, such as sarin nerve gas.

Vice-President Dick Cheney says the US knows al Qaida has been training terrorists to use chemical and biological weapons.

He commented: "We have copies of the manuals that they've actually used to train people with respect to how to deploy and use these kinds of substances."

Gary Ackerman, a terrorism expert with the Centre for Nonproliferation Studies, says it is unlikely an attack using low-tech poison gases would kill large numbers of people because doctors can treat victims with oxygen.

He commented: "These are your basic kindergarten-version chemical weapons.

"They are the easiest to get a hold of and produce. They are also the least fatal ones."