BOSTON (CBS) – Passengers on a crowded Orange Line train were forced to evacuate into a tunnel near North Station Thursday morning after a small fire broke out.

It happened just before 11 a.m. about 200 feet past the platform heading towards Haymarket station, according to the fire department.

WBZ-TV’s Ron Sanders Reports

There was a small grease fire under a train. It was out by the time firefighters arrived.

WBZ News Radio 1030′s Mark Katic reports

No one was hurt, but power to the train was cut off so all 200 passengers had to get out and walk back to North Station through the tunnel. They were escorted by firefighters and all six cars were empty by 11:43 a.m.

The fire department described the process as “orderly.”

Orange Line service resumed just after noon.