Read as much as you want on BostonGlobe.com, anywhere and anytime, for just 99¢.

Factory explosion believed to have ignited in acid room

PETERBOROUGH, N.H. — A factory explosion that blew out windows and injured more than a dozen people probably originated in a room where acid is used to treat the surface of ball bearings, but it could be weeks before the exact cause is determined, investigators said Tuesday.

The blast Monday afternoon at New Hampshire Ball Bearings Inc. shattered glass, dislodged ceiling tiles, and damaged walls.

Continue reading below

The building, however, was stable enough for investigators to work inside Tuesday.

Deputy Fire Marshal Max Schultz said the on-site investigation was expected to end later in the day.

The building was then to be turned over to company officials for cleanup and repairs.

The plant makes parts for the aerospace industry and employs 700 people.

Company spokeswoman Kathy Gerrity said there would have been about 450 working at the time of the blast, which happened just after a 3:30 p.m. shift change.

No one was in close proximity to the explosion, Schultz said.

Loading comments...

You have reached the limit of 5 free articles in a month

Stay informed with unlimited access to Boston’s trusted news source.

  • High-quality journalism from the region’s largest newsroom
  • Convenient access across all of your devices
  • Today’s Headlines daily newsletter
  • Subscriber-only access to exclusive offers, events, contests, eBooks, and more
  • Less than 25¢ a week