In United States, a powerful explosion blew out the outer walls of an unfinished natural-gas plant in Middletown, Connecticut, killing five persons and wounding dozen others. Rescuers were hunting for survivors and dead in the Kleen <br/><br/>Energy Plant as officials cautioned that they did not know how many people were in the plant when the explosion went off.<br/><br/>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.<br/><br/>Rescue workers were being helped by dogs to search the rubble and so far 12 people had been admitted to hospital with injuries.<br/><br/>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 a.m Sunday.<br/><br/>Official said the explosion occurred when workers were purging the gas from the pipelines, a procedure called a blow down.