NEW YORK — Police investigating a potentially devastating car bomb attack in Times Square were focused Sunday on finding a man who was videotaped shedding his shirt near the SUV where the bomb was found.
The video shows an unidentified white man in his 40s slipping down an alley on Saturday evening, taking off one shirt and revealing another underneath. In the same clip, he's seen looking back in the direction of the smoking vehicle and furtively putting the first shirt in a bag, police Commissioner Raymond Kelly said.
The homemade bomb was made largely with ordinary items including three barbecue grill-sized propane tanks, two 5-gallon gasoline containers, store-bought fireworks and cheap alarm clocks attached to wires. If successfully detonated, police said at a minimum it would have sprayed shrapnel and metal parts over one of America's busiest streets, full of Broadway theaters and restaurants, on a Saturday night.
New York City police say they also found more than 100 pounds of fertilizer in the SUV but it was incapable of exploding, unlike the ammonium nitrate fertilizer used in the Oklahoma City bombing.
But the effects could have been horrifying.
Kelly said the bomb "looks like it would have caused a significant fireball" had it fully detonated. He said the vehicle would have been "cut in half" by an explosion and people nearby could have been sprayed by shrapnel and killed.
Federal authorities said the incident appeared isolated and that there was no evidence of an ongoing threat to the city.
"We are treating it as if it could be a potential terrorist attack," Janet Napolitano, the Homeland Security secretary, told CNN, one of several TV appearances she made Sunday. The bomb itself was not a sophisticated device, she said on ABC's This Week. "Right now, we have no evidence other than it is a one-off."
A Pakistani Taliban group claimed responsibility for the failed attack in a 1-minute video. Kelly, however, said police have no evidence to support the claims, and noted that the same group had falsely taken credit for previous attacks on U.S. soil. The commissioner also cast doubt on an e-mail to a news outlet claiming responsibility.
The New York Police Department and FBI were examining "hundreds of hours" of security videotape from around Times Square, Kelly said.
Police released a photograph of the SUV, a dark-colored Nissan Pathfinder, as it crossed an intersection at 6:28 p.m. Saturday.
Duane Jackson, a 58-year-old handbag vendor from Buchanan, N.Y., said he noticed the SUV, parked with the engine running, hazard lights flashing and the driver nowhere to be found.
Jackson said he alerted a passing mounted police officer.
They were looking in the car "when the smoke started coming out and then we heard the little pop-pop-pop like firecrackers going out and that's when everybody scattered and ran back," he said.
Police said they had identified the registered owner of the Pathfinder, but hadn't spoken to him yet. The license plate found on the vehicle did not belong to the SUV; police said it came from a car found in a repair shop in Connecticut.
The Pathfinder was taken to a forensics facility in Queens, where investigators were scouring it for DNA evidence and hairs, fibers and fingerprints.
FBI agents and detectives from the Joint Terrorist Task Force were also trying to determine where the attacker bought the three canisters of propane and two red plastic five-gallon containers of gasoline.
Initially, investigators thought the last owner was in Texas and had donated the car to a charity in North Carolina, one official said. But they later learned that the owner was in Connecticut.
The license plate on the SUV was traced back to a different vehicle that was awaiting repairs in Stratford, Conn., where FBI agents and the local police awoke the owner of the repair shop at 3 a.m. Sunday.
The shop owner, Wayne LeBlanc, who runs Kramer's Used Auto Parts, said that the authorities seized a black Ford F-150 pickup truck. "We're trying to help them identify who took the plates," he said.
Investigators also were reviewing similarities between the incident in Times Square and coordinated attacks in the summer of 2007 at a Glasgow airport and a London neighborhood of nightclubs and theaters. Both attacks involved cars containing propane and gasoline that did not explode. Those attacks, the authorities believed, had their roots in Iraq.
Information from the New York Times and Associated Press was used in this report.