An explosion at the almost completed Kleen Energy power plant in Middletown, Conn. killed five people and injured at least 12 others. Search and rescue teams remained on the scene Sunday night in hopes of finding any other workers who may have been buried in debris.

Click on the four-arrows on the bottom right corner of the video to enlarge to full screen and view in high definition.

Middletown Mayor Sebastian Giuliano said an estimated 100 to 200 people could have been working on the site at the time of the blast around 11:30 a.m. today. Adding to the confusion after the explosion was the fact that there were multiple contractors working on the site, which officials say was 95 percent complete. Middletown officials said they are working with contractors to get a complete list of workers.

Middletown Deputy Fire Marshal Al Santostefano said that the blast occurred while workers were purging the gas lines. During that process of cleaning out the lines, “something ignited gas,” Deputy Fire Chief Mark Fongemie said. 

Officials did not release the names of the five people killed pending notification of family members. The Red Cross set up a family information hotline today at 860-347-2577.

Giuliano said terrorism has been ruled out as a cause of the explosion.

Rep. Matt Lesser, who lives about a mile from the plant, said he heard the loud blast this morning. “It shook the windows,” he said.

At a press conference Sunday evening, Lesser said he has been responding to texts and phone calls all day.  He said he spoke with workers at the adjacent Pratt and Whitney facility, which had stopped working when they heard the blast because they thought it had come from inside their own facility.

Rep. Joe Serra of Middletown said construction on the plant started more than a year and a half ago. It took about nine years to permit and it planned to open in May or June, he said.

Congresswoman Rosa Delauro said the Department of Health and Human Services and Homeland Security have been monitoring the response to the explosion all afternoon. She said the federal government will do anything it can to help coordinate resources.

Energy Investors Funds, a private equity fund that owns a majority share in the $985 million power plant, started construction on it in February 2008. The plant is 620-megawatt facility being built to feed electricity to Connecticut Light & Power under a 15-year power purchase agreement, according to the Energy Investors Funds Web site.

“Energy Investors Funds wishes to express our enormous sympathy and concern for the workers at the Kleen Energy plant and their families,” a spokesman said in an emailed statement. “We strongly value their contributions, efforts and dedication. We are fully cooperating with authorities, and will provide further comment once more information becomes available.”

Late Sunday evening, Gov. M. Jodi Rell who visited the scene earlier in the day sent out a statement announcing that the state has secured a temporary no-fly zone over the site of the explosion because of the instability of the heavily damaged building.

The flight restrictions are in effect until 5:21 p.m. Monday, February 8, and extend to a three nautical mile radius below 3,000 feet.

The video above was shot from a helicopter for, LocalOnlineNews.TV, and the Journal Inquirer, and shows that the explosion – which was felt by residents all over the southern half of Connecticut – blew most of the sheet metal walls off the plant’s main building.

Watch for a follow-up stories on the victims, the power plant’s future, and the state’s clean energy plans.