NEW YORK (CBSNewYork) – A manhole explosion at a construction site closed a busy section of Midtown during the evening rush Thursday.

Firefighters responded to the site, near Sixth Avenue and West 47th Street, just before 4 p.m.

READ MORE: RFK Bridge Lanes Closed After Police-Involved Shooting, Trooper Struck By Vehicle

Two workers were hurt in the blast, but neither of the injuries was serious.

READ MORE: Police: 2 Women Killed In Single-Car Crash In North New Hyde Park

There is no word yet on what caused that explosion.

MORE NEWS: Giants' Defense Forces 4 Turnovers In Win Over Eagles