Federal law enforcement officials say they have numerous credible leads in their probe of Tuesday's airborne terrorist assault on New York and Washington. Authorities believe some of those who hijacked and crashed four jetliners knew how to fly them.
In a brief press conference Wednesday, Attorney General John Ashcroft and new FBI chief Robert Mueller said the investigation is making progress.
Mr. Mueller said many of the hijackers now have been identified. "We also have identified through a number of leads, principally at the cities of origin, a number of individuals who we believe may have had something to do with the hijacking and we are pursuing those leads aggressively," the FBI chief said.
Mr. Mueller denied reports that suspects are in custody, though he said some people have been detained because of questions about their immigration status. The reports surfaced after police raided a Boston hotel and later stopped a train bound from Boston to Washington. Two of the planes involved in the strikes took off from Boston.
Attorney General Ashcroft offered a few details of how the operation was carried out. He said some of the hijackers were trained to fly in the United States. "The four planes were hijacked by between three and six individuals per plane, using knives and box cutters and in some cases making bomb threats," he reported.
Mr. Ashcroft also confirmed reports the terrorists targeted the White House and the president's plane, Air Force One. He did not say who might have masterminded the strikes which brought down the World Trade Center and tore a huge gash in the Pentagon.
Some officials are quoted as saying the evidence points to exiled Saudi financier Osama bin Laden. A number of lawmakers are demanding retaliation against both bin Laden and Afghanistan, where his organization is based. However, there is no definitive word on who is believed responsible for the attacks.