Updated 12/02/10 at 7:40 p.m.

CHICAGO (STMW) – Residents of a Northwest Side block have been allowed back into their buildings after a gas main leak forced them out for close to two hours Thursday evening.

A Level II HazMat response was called just after 5 p.m. at 1858 N. Oak Park Ave., according to Fire Media Affairs spokesman Quention Curtis. As of 5:50 p.m., firefighters had evacuated the entire block.

“There is a medium gas main leaking and everybody is being evacuated,” Curtis said at 5:55 p.m. “CTA warming buses have been called to house the evacuees.”

People’s Gas spokeswoman Kathy Hartman said crews were on the scene of a gas main break, the cause of which is unknown.

“We are just focusing on getting it fixed right now,” she said about 6:40 p.m. “We had to shut down gas service to a portion of the area.”

Firefighters were able to secure the HazMat about 7:20 p.m. after People’s Gas stopped the leak. All residents were then allowed to get back into their homes, Curtis said.

No injuries were reported and there was no explosion, Curtis said.

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