Fire crews responded to the regional headquarters of Eastern Bank in Lynn this morning after reports of an explosion.
Firefighters responded to the Market Street office building before 10:30 a.m.
Scores of people had to be evacuated. Pictures from the scene showed smoke coming from the building.
On its Facebook page, the bank called the incident an "electrical mishap" at its operations center and that phone and e-mail services may suffer from sporadic outages.
The company's north region headquarters is located at the building.