INDIANAPOLIS (AP) - Officials say as many as 31 homes were damaged so badly in a blast and huge fire that killed two people in Indianapolis that they may have to be demolished.

Deputy Code Enforcement Director Adam Collins estimated the damage at $3.6 million.

Deputy Fire Chief Kenny Bacon told reporters Sunday investigators haven't ruled out any possible causes of the late-night blast that was heard miles away.

But a congressman who represents the Indianapolis neighborhood says investigators have ruled out a bomb or a meth lab.

U.S. Rep. Andre Carson said he had received that report from Homeland Security officials during a tour of the devastated middle-class subdivision. 

Residents described a loud boom that shook their homes, blew out windows and collapsed ceilings.

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