RUMFORD – Shortly before 5:30 p.m. Saturday, Rumford firefighters responded to the Central Maine Power substation at the top of Falls Hill after a passerby on Route 2 witnessed an explosion and contacted authorities.

But when they arrived, a CMP crew already working there, told them to leave, fire department Deputy Ben Byam said in a telephone interview about four hours later.

“They were doing some work up there and something happened and something exploded,” he said. “They were switching it one way and another. They told us to get out of the area, because they were worried about another explosion, about porcelain hitting our firetrucks.”

A CMP spokesman contacted Saturday night said the crew was working on a hot insulator, but she didn’t know there’d been an explosion.

Electricity in the area was knocked out for 30 minutes, she added.

Additionally, another CMP crew was sent to Hanover after a car went off Route 2 and struck a utility pole at 8:38 p.m. Saturday.

Byam said Rumford firefighters had a busy day, but weren’t sent to the Hanover accident. During a nearly eight-hour standoff between police and a man threatening to burn his former wife’s house down at 139 Penobscot St., firefighters stood by throughout the ordeal.

“We were there just in case,” he added.