Manhattan hospitals were put on full disaster alert and prepared to decontaminate incoming victims from radiation, with at least one scanning them with a Geiger counter.

Fearing a new terrorist attack, the FBI and the New York bomb squad swooped on the ten-storey building on West 19th Street in response to the blast shortly before noon. The surrounding streets were cordoned off and emergency crews and more than 100 firefighters set up a triage centre on the pavement for dozens of walking wounded.

St Vincent’s Hospital, which treated the injured from the World Trade Centre on September 11, declared its top “Code Three” disaster alert as its safety officer monitored arriving victims for radiation in a decontamination area. Federal officials gave warning recently that al-Qaeda may be trying to develop a radiological device, or “dirty bomb”, for attacks in the United States.

Six people were admitted to the hospital in “very critical condition” with head wounds and burns, after the blast which injured up to 50. Windows along the block were blown out by the force of the explosion and several of the injured were hit by flying glass. More than 100 firefighters were called to the scene.

But Dr Richard Westfal, the associate director of St Vincent Hospital’s emergency room, said: “There was no evidence of any weapons of mass destruction or anything like that. It looked like just an explosion.”

The blast rattled nearby buildings and was initially thought to have occurred in the Apex Technical School on the corner of West 19th Street and 6th Ave. The school was not damaged.

Bill Beek, who lives a half-block away, said: “It was a real giant boom, It sounded like an airplane crashing.”

One eyewitness, Alan Awol, said: “I heard a big explosion. The whole third floor had collapsed. People were stuck on the third floor. They looked like they were hysterical, like they wanted to jump out.”

Scott Bonilla, a student at the technical school, said he was inside the building when it began shaking. “They told us to rush out of the building,” he said. Stuart Markowitz, who runs the school’s education department, said: “It was just a really loud noise. Some of our windows did get blown out.”

Michael Bloomberg, the New York Mayor, said: “At the moment I want to assure that there is absolutely no reason to think this is anything other than a tragic accident, and we hope there is no loss of life.”

Like the jet crash near John F. Kennedy airport late last year, the blast rattled New Yorkers’ nerves and offered another test of the city’s revamped emergency response system.

Nicholas Scoppetta, the New York Fire Commissioner, said that the explosion occurred in the basement of the building, which houses a company that makes signs. He said the company received shipments of volatile materials in 50-gallon drums on Wednesday but could not say if those were the cause of the explosion. According to earlier reports, the New York City building department had received a complaint about unauthorised construction at the site and inspectors had issued a “stop-work” order on Tuesday. Despite the ban, work apparently continued.

Copyright 2002 Times Newspapers Ltd

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