Washington, Feb 02: Intelligence suggested al Qaeda may try to attack with a chemical or biological agent aboard an airplane, prompting several US-bound flights to be canceled, the Washington Post reported today, citing unnamed administration officials. Three intelligence officials described to the newspaper that the possible threats included releasing an undetected biological agent like smallpox or anthrax onboard in the hopes those onboard would spread it without knowing it.

The officials also said attackers could try to hijack a plane by releasing a chemical agent to incapacitate the crew and passengers or smuggle a radiological device in luggage, the Post said.
The newspaper said the intelligence on a possible attack with a weapon of mass destruction was vague.
Continental Airlines canceled its Sunday flight from Glasgow in Scotland to Newark because of security concerns.
British Airways canceled a London to Washington flight for Sunday and Monday as well as its return trip and scrapped a Sunday flight from London to Miami.
The London-Washington flight was the same one that was canceled several times early in January amid security concerns. Air France canceled its Paris to Washington flight for those two days as well for safety precautions.
A US official said on Saturday Osama bin Laden's al Qaeda network, blamed for the September 11, 2001, attacks, may now be targeting five or six US-bound flights from Europe.
US officials demanded enhanced security precautions that some airlines could not take so ''it became easier to just cancel the flights,'' an administration official told the Washington Post.
Since the flights were scrapped, the US Department of Homeland Security decided against deploying crews to detect hazardous materials, the newspaper said.
Bureau Report