Powerful explosions caused by an overturned gas tanker rocked New York city at noon Monday, police said.

Fox TV reported that a gas truck crash had caused the explosions, broadcasting a footage showing a burning gas truck lying on its side just under a bridge of the Line 7 railway, with firefighters sprinkling where heavy smoke was billowing from.

Part of the blackened railway tracks was seen dangling under the bridge, apparently burnt down by some 8000 gallons of gas reportedly carried by the underlying truck.

A police officer near the site would not confirm if people were injured or if it was a terrorist attack, saying that nothing else was known other than that it was caused by a gas tanker which has caught fire.

A call by Xinhua to NYPD's press inquiry also brought no definite explanations. Asked about the cause of the explosions and any possible casualties, an unidentified officer simply said the explosion happened sometime ago before hanging up.

The gas tanker was seen on fire on a highway between No. 69 and No. 74 subway stations on the Roosevelt Avenue, Queens. Heavy smoke billowing into the sky was once seen even by Xinhua reporters at the United Nations headquarters in Manhattan.

About more than one hour after the start of the incident, no smoke could be seen in the sky above the burning site, suggesting the fire might have been put out.

The police have cordoned off the area and closed the nearby subway stations.

At least six tremendous explosions were heard at Xinhua's New York Bureau, which is only dozens meters away from the scene.

(Xinhua News Agency January 17, 2006)