After years of experiments, Al Qaeda is now capable of constructing “dirty bombs” and appears ready to launch terrorist attacks using the radioactive devices along with deadly chemical weapons, counter-terrorism authorities said Friday. Since the attacks on the World Trade Center and the Pentagon nearly 17 months ago, U.S. officials have publicly stated their fears that the global terrorist network headed by Osama bin Laden was trying to acquire and use such devices. But they maintained that Al Qaeda did not have the technology, particularly to launch so-called dirty bombs, which use conventional explosives encased in radioactive waste. When detonated, such portable bombs could disperse significant amounts of radiation, causing poisoning and contamination over a widespread area. Full Story