WEST READING (AP) – Federal safety investigators have determined that natural gas was leaking from a defective fitting at a Berks County chocolate factory where a powerful explosion killed seven people. The National Transportation Safety Board, which has yet to determine the cause of the March 24 blast, said that the leak at the R.M. Palmer Co. plant in West Reading was traced to a gas fitting installed in 1982. Investigators say the fitting had a known tendency to crack. Investigators also found a small leak on a gas fitting installed in 2021. Factory employees have told federal investigators they could smell gas before the explosion.