WEST READING, PA.  — The National Transportation Safety Board is investigating a March 24 explosion at an R.M. Palmer Co. candy factory in West Reading that led to seven deaths. Preliminary information shows a pipeline in the factory was transporting natural gas, according to the NTSB, which described a pipeline as a form of transportation that carries products.

The NTSB will work with local authorities and utilities companies and will examine the pipeline for fractures. A preliminary report should be available in less than a month. The investigation may take 12 to 14 months to complete.

The R.M. Palmer Co. has more than 800 employees and offers over 500 products, including seasonal favorites such as Mummy Munchies for Halloween, Frosty the Snowman novelties for Christmas and chocolate hearts for Valentine’s Day.

“Everyone at R.M. Palmer is devastated by the tragic events at one of our West Reading facilities, and we are focused on supporting our employees and their families,” the R.M. Palmer Co. said. “We have lost close friends and colleagues, and our thoughts and prayers are with the families and friends of all who have been impacted. We are sincerely grateful for the extraordinary efforts of all of the first responders and for the support of our Reading community, which has been home to our business for more than 70 years.”