Utility crews work at the site of a gas leak at 4350 N Broadway on Tuesday, Nov. 22, 2011.  (Brian Cassella/ Chicago Tribune)

Utility crews work at the site of a gas leak at 4350 N Broadway on Tuesday, Nov. 22, 2011. (Brian Cassella/ Chicago Tribune)

A construction crew on the North Side broke a large gas main late this morning, prompting a hazardous material alert, a precautionary building evacuation and a partial shutdown of Red Line service.

The break happened about 11 a.m. at 4350 N. Broadway Ave. in the Buena Park neighborhood, according to Fire Department media affairs. A Level 2 hazmat situation was called and the matter was under control about 20 minutes later, officials said.

CTA Red Line service between Wilson and Addison had been shut down briefly and buses were shuttling passengers. By 11:45, Red Line service was back to normal, a CTA spokeswoman said.

Fire spokesman Richard Rosado said initially that they were waiting for the gas company officials to be called to shut the gas off.

A building had also been evacuated strictly as a precaution, Rosado said.

chicagobreaking@tribune.com