The mayor of Middletown, Conn., says five people are known dead in a gas explosion at a power plant there. No one else is believed to be in the rubble

Mayor Sebastian Giuliano says at least 12 people are known injured from Sunday's blast at the Kleen Energy Systems plant as workers purged natural gas lines. The plant is under construction.

A deputy fire marshal told The Associated Press before a news conference Sunday evening that crews were still searching for survivors in the rubble.

The mayor says it's hard to tell how many people were at the plant because multiple contractors were working on it with their own employee lists. Officials earlier said about 50 people were in the area at the time of the explosion.

The blast rattled homes for miles. One woman who lives nearby says she heard a "tremendous boom." Another Middletown resident says he "felt the house shake," and thought a tree had fallen on his home.

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