Unexploded shells left behind by fireworks company detonate in three Massachusetts towns

By Matt Woolbright, Globe Correspondent

City workers mowing lawns in three Massachusetts communities ran over unexploded fireworks shells left behind after July Fourth shows, causing the shells to detonate under the workers’ lawnmowers.

Though the workers avoided serious injury, state fire authorities have suspended the license of the fireworks company responsible for leaving the unexploded shells near the launching grounds for their shows.

State Fire Marshal Stephen Coan said today that the size of the lawnmowers protected the workers as the shells exploded.

“If someone were to pick this up, or hit it with less than a commercial mower, the outcome could have been different,” Coan said.

The unexploded shells were left behind by a Pennsylvania-based company called Pyrotecnico, Coan said. He said an investigation was underway to determine if the actions were a violation of the state fire code, which requires companies to search for unexploded shells the morning following a show.

The first mower struck a shell in a park in Ware on July 6. Workers searched the area that afternoon and found three more unexploded shells left over from the town’s June 30 fireworks show. Later, the same worker ran over another shell that had not been discovered in the first search. A subsequent search revealed two more unexploded shells.

On Monday, another worker operating a lawnmower hit a shell in Waltham. In Stoughton, another worker ran over a shell. A search in Worcester found yet another unexploded shell.

The shells in Ware were mostly found in a wooded park frequented by children, said Deputy Fire Chief Dan Danitis.

“We didn’t want anyone to pick one up and try to see what’s inside, and then get hurt or killed,” Danitis said.

Tuesday evening, Coan issued an order suspending Pyrotecnico’s licence to operate in Massachusetts. The order included a demand that the company return and search for unexploded shells in the 13 Massachusetts locations where it staged shows.

The other towns where Pyrotecnico staged displays were: Ayer, Hingham, Marion, Milford, Newton, Westford, Willmington, Winchester, and Sharon.

Coan also suspended the license of the Pyrotecnico employee who shot off the fireworks at the Ware show.

“They are commercial-grade pyrotechnics, so they are very dangerous,” Coan said. “It’s important that people who see what could be a shell do not touch it, pick it up or go near it, but call 911 and let emergency officials take a look.”

As of 2:30 p.m. today, bomb experts were on their way to Stoughton after another report of a shell being discovered.

Matt Woolbright can be reached at matt.woolbright@globe.com. Follow him on Twitter @reportermatt