Emergency responders and heavy equipment are seen at the site of a deadly explosion at a chocolate factory in West Reading, Pennsylvania, Saturday, March 25. (AP Photo/Michael Rubinkam)

WEST READING, Pa. (AP) — Federal safety investigators are looking at a natural gas pipeline for fractures and other damage as they gather evidence on the cause of a deadly explosion at a Pennsylvania chocolate factory. The National Transportation Safety Board opened a probe into Friday’s blast at R.M. Palmer Co., which killed seven, wounded several others and leveled the building in West Reading. An agency spokesman said Wednesday that safety investigators are gathering evidence about the pipeline. The family that owns the factory says the loss of their employees “will be felt forever.” A coroner is set to release the names of most of the victims later Wednesday.