A huge explosion at a Connecticut power plant killed at least two people andcaused mass casualties — and one witness describing the scene said, "there are bodies everywhere."

Details on the number of injuries and fatalities varied according to different reports and various officials.

Al Santostefano, Middletown Deputy Fire Marshal told NewsCore that 50 construction workers were at the Kleen Energy power plant when the explosion occurred. Santostefano confirmed that there were fatalities and injuries, but could not confirm the number of injured or dead.

AP/middletown press

Smoke comes from the the Kleen Energy plant on River Road in Middletown, Conn. Multiple people have died in an explosion an unknown number of people are injured.

AP/hartford courant

Area fire and ambulance crews arrive near the scene.

He told the Hartford Courant the devastating blast occurred as workers attempted a "blow down," or purge, of natural gas pipelines. Early reports are that the cause was a gas leak.

The search and rescue efforts are ongoing, Santostefano told NewsCore. He said he did not know of any plant workers at the location during the blast. He also said people may be trapped underneath the rubble and that emergency officials were conducting search and rescue operations.

The Hartford Courant reported medical rescue personnel as saying that there were at least two fatalities, and as many as 100 people injured, including four in critical condition. The paper also reported that as many as 20 ambulances were on scene and quoted a witness as saying "there are bodies everywhere."

The Connecticut Post reported that four people were pulled from the rubble with life-threatening injuries and a source at the scene told the Post that the death toll will rise beyond two.The Post also reported a source on scene as saying that the search and rescue operation had turned into a recovery operation as state police were on scene with rescue dogs.

Local affiliate WFSB reported that 2 had died and 250 were injured in the explosion.

Viktoria Sundqvist, managing editor of the local newspaper The Register Citizen, told Sky News that she had heard a report from an emergency worker on scene that up to 34 people had died and 100 were wounded.

The power plant is not currently [in] operation. The plant has been under construction and is not yet online. The plant's general manger Gordon Holk told WVIT that the plant is a 620 megawatt gas-fired power plant. Fire officials on scene confirmed that the plant was connected to a natural gas pipeline.

Police Sgt. Chuck Jacobucci told NewsCore there are mass casualties, but police don’t know how many people were in the building when the explosion occurred and if the people were plant employees or construction workers. Tests were being performed in the plant Sunday but Jacobucci said he did not know if gas was involved in the tests.

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