A powerful explosion blew out the outer walls of an unfinished natural-gas plant in
Middletown, Connecticut, killing five people and wounding dozen others.
Rescuers were hunting for survivors and dead in the Kleen Energy Plant as officials cautioned that they did not know how many people were in the plant when the explosion went off.
Terrorism has been ruled out, according to the Middle Town Mayor Sebastian N Giuliano, who said the explosion was so loud it could be heard almost for miles around.
"The mayor has been assured that this is an industrial accident and no terrorism is suspected," said a statement from his office.
Rescue workers were being helped by dogs to search the rubble and so far 12 people had been admitted to hospital with injuries.
"It was like a fire ball going up with a lot of smoke," neighbours told television channels and said most of their windows were blown away or shattered by the impact of blast.
It is estimated that 50 construction workers were in the part of the building that was blown away during the explosion that occurred a little after 11.15 am on Sunday.Officials said the explosion occurred when workers were purging the gas from the pipelines a procedure called a blow down.