(Middletown, CT) -- Five people were killed Sunday in a massive natural gas explosion at a power plant under construction in Middletown, Connecticut. The explosion took place at the Kleen Energy plant along the Connecticut River. The blast was felt for miles around, and some victims reportedly were blown 30 to 40 feet away by the force of the explosion. There were about 50 people working at the plant at the time of the blast. The huge plant was 95-percent complete and was scheduled to go online over the summer.