Associated Press People are evacuated by the New York Fire Department as other firefighters enter a floor of a 10-story building where an explosion took place Thursday, in New York. The explosion, possibly caused by volatile chemicals in its basement, injured 32 people Thursday morning as it sprayed glass and rubble across a quiet block in the Chelsea section of Manhattan.

NEW YORK ÷ An explosion rocked a 10-story commercial building yesterday, spraying glass and rubble across a quiet block and injuring as many as 50 people, authorities said.

ãIt was a giant boom ÷ a real giant boom,ä said neighborhood resident Bill Beek, who lives a half-block away.

ãIt sounded like an airplane crashing.ä

Several victims, at least three in serious condition, were taken to four Manhattan hospitals for treatment. One hospital, St. Vincentâs, reported it was treating eight patients, six of whom were critically injured.

Other victims, bloody and bandaged, sat on curbs waiting for transportation.

A preliminary injury total stood at 50, said police spokesman Michael OâLooney.

A tally of hospitals showed at least 20 people were taken to four of them; other people were treated at the scene.

Plumbers were working on the boiler in the commercial building at 121 W. 19th St. at the time of the 11:30 a.m. blast, but it was unclear if that was the cause of the explosion.

Windows along the block were blown out by the force of the blast, and several of the injured were hit by flying glass. The facade of the building was blown off; it was unclear how much of the buildingâs interior had collapsed.

Scott Bonilla, a student at the nearby Apex Technical School, said he was inside the building when it began shaking.

ãThey told us to rush out of the building,ä he said.

ãThere was like an explosion ... and I ran out of there.ä

Law enforcement officials said it did not appear to be an act of terrorism.

ãIt was just a really loud noise,ä said Stuart Markowitz, who runs the technical schoolâs education department. ãSome of our windows did get blown out.ä

All students were safely evacuated, he said. Initial reports that the explosion took place inside the school itself were not true, he said.

Sid Dinsay, spokesman for the city Office of Emergency Management, said the building housed commercial tenants, including a sign company.

Power was cut off to two buildings on the block at the request of the fire department, and officials asked for voluntary evacuation of the rest of the street.

More than 100 firefighters were called to the scene.