NEW YORK (CBSNewYork) — A high-pressure steam pipe exploded in the Flatiron District Thursday morning, ripping apart the pavement and sending large plumes of steam pouring into the air.

The 20-inch pipe burst around 6:40 a.m. on Fifth Avenue between 22nd and 21st streets.

Fire Commissioner Daniel Nigro said the pipe was installed in 1932 and officials are now concerned about the possible presence of asbestos.

“Samples have been taken and we’re awaiting lab results of those samples but we are operating as if the samples will come back positive,” he said.

As a precaution, Con Ed is urging anyone in the area at the time of the blast who may have been covered in any debris to bag their clothes and take a shower.

Nigro said two decontamination stations have also been set up at 22nd Street and at 19th Street.

“Anyone who feels like they were affected by this and possibly contaminated can report there for evaluation,” he said.

More than 100 firefighters responded to the scene along with the NYPD and crews from Con Ed. A large hole could be seen in the street where the explosion occurred.

Nigro said 28 buildings in the area were evacuated, adding they will “remain evacuated for a while.”

Five people also suffered minor injuries, including three civilians from the debris, Nigro said.

Officials said it could take days to clean up the area and people should continue to expect traffic delays, road closures and emergency personnel at the scene.

Fifth Avenue southbound from 25th Street to 19th Street, Broadway southbound from 23rd Street to 17th, 19th Street to 22nd Street from Sixth to Fifth avenues and 23rd Street from Sixth to Park Avenue are all closed.