NEW YORK - A neighborhood in Manhattan, New York City, was rocked Thursday morning when a steam pipe exploded, causing transit disruptions and street closures.

The blast occurred at about 6:40 am (1040 GMT) Thursday near Fifth Avenue and 21st Street, just blocks from the iconic Flatiron Building. It left a crater in the middle of the street and sent massive plumes of smoke into the sky over the city.

The New York Fire Department responded to the explosion. No injuries were reported.

The cause of the blast is under investigation.