A witness who says he saw a sniper fire with an assault rifle and flee in a cream-colored van gave a phony story, investigators said Thursday in a setback that casts doubt on much of what the public thought it knew about the roving killer.
Prosecutors are investigating the witness, whose name wasn't released, to determine whether he should be charged with filing a false statement.
Fairfax County police Lt. Amy Lubas said the inaccurate account was exposed by checking it against that of other witnesses to Monday night's killing of a woman in a crowded Virginia parking lot outside a Home Depot. It is the only shooting people have seen.
Investigators had showed a certain optimism after the latest attack seemed to yield the best details about the killer. But that gave way to anger Thursday.
Montgomery County police Chief Charles Moose said there was no credence to the witness' description of the cream-colored van with a burned-out rear taillight. And while Moose did not give the witness' exact description of the shooter, he chastised reporters for running reports that had various descriptions.
"When we have people from the media interviewing witnesses and publishing reports, we get confusion," Moose said. "We get this noise . . . out there that gives people tunnel vision and makes them focus in on things that are not appropriate."
Moose said the witness' description of the shooter's AK-74 assault rifle is bogus. But investigators cautioned they believe the sniper is using one of a family of more than 30 similar assault-type weapons capable of firing a .223-caliber bullet.
"The message we're trying to say is please keep an open mind," Moose said. "People saw a description of a weapon over the last day and a half and we're convinced they eliminated people they know because they say, "Their gun is not the weapon I saw in the paper.' "
Mike Bouchard, a special agent with the federal Bureau of Alcohol, Tobacco and Firearms, said each gunmaker has a number of models that look the same, and different accessories can make one gun look like another.
Moose said the disclosure of the fake story, coming a day after investigators said they were unable to draw a composite sketch, was hardly a setback. He said investigators are chasing leads and he stood by previous composite drawings of vehicles witnesses reported seeing leaving the attacks: a white box truck and a Chevrolet Astro van or Ford Econoline van.
After two massive police dragnets failed to catch the killer, Virginia police doubled their patrols outside Washington, police spokeswoman Lucy Caldwell said.
Investigators returned to the Home Depot parking garage Thursday to make another sweep for evidence. At a parking lot across the street, police stopped all vehicles as they left and officers appeared to crouch down to search beneath them.
Since Oct. 2, there have been 11 shootings in Maryland, Virginia and Washington, D.C., that have left nine people dead and two wounded. One of the two surviving victims, a 13-year-old boy, was upgraded from critical to serious condition Thursday in a Washington hospital.
Also Thursday, several news outlets, citing government sources, reported federal investigators are planning to question al-Qaida prisoners in Guantanamo Bay, Cuba, about the attacks to explore possible terrorism links. The sources said that the interviews were not prompted by evidence the shootings are connected to foreign terrorism but that they were simply a prudent step.
Defense Secretary Donald Rumsfeld would not confirm the reports, saying only, "I have no information that (the sniper case) is terrorist-related."
_ Information from Cox News Service was used in this report.