'Mass casualties' fear as blast rips through US power plant

Ambulances from across the region and several helicopters rushed to the Kleen Energy Systems LLC plant on the banks of the Connecticut River after the blast.

People living several miles away reported that their homes were shaken by the explosion at the plant, which is being built outside Middletown.

Black smoke could be seen pouring out of the plant shortly after the explosion.

Last night, search and rescue teams were dispatched after growing fears that some people might still be trapped under the rubble. Hospitals were on high alert.

Officer Kevin White of Middletown police said there were "mass casualties".

Middletown Mayor Sebastian Giuliano confirmed five people had died and at least 12 had been injured. The mayor said it was difficult to tell how many people were at the plant because multiple contractors were working on it with their own employee lists.

He said: "They're trying to figure out who was on the job today, and where are they now?"

A fire official said 51 construction workers were believed to be on site at the time.

Brian Albert, spokesman for the local Middlesex Hospital, said 11 people were admitted.

Two were later released, eight were treated for broken bones, abdominal injuries, blunt force trauma and similar injuries.

The explosion happened just before 11:30 yesterday morning local time during tests at the site, a 620 megawatt gas-fired power plant which was due to come online in the summer.

Workers at the power plant were purging natural gas lines.

Connecticut governor Jodi Rell activated the state emergency operations centre in Hartford, the state capital.

The Department of Public Health was providing tents for medical equipment and shelter with temperatures near freezing point.

Lynn Hawley, 54, of Hartland, Connecticut, said her son, Brian Hawley, 36, was a pipefitter at the plant. He called her to say he was being rushed to Middlesex Hospital.

"He really couldn't say what happened to him," she said. "He was in a lot of pain, and they got him into surgery as quickly as possible."

She said he had a broken leg and was expected to survive.

Residents felt the blast, which some said hit with the force of an earthquake, for miles. "The whole house shook. I didn't know what it was, whether it was the house or the water heater or what.

"Everything shook," said Cornelia Hull, who lives about a mile from the plant.

Some residents reported windows blown out by the force of the explosion.

The blast was felt as far as 30 miles away.