BOSTON — The Red Sox and Bruins postponed their games Friday as authorities searched for a suspect in the Boston Marathon bombings, virtually shutting the city down.

The teams announced about four hours before their night games were scheduled to start that they were scratched.

The NHL game at TD Garden between the Bruins and the Pittsburgh Penguins, two of the top four teams in the Eastern Conference, was tentatively rescheduled for Saturday at 12:30 p.m. A final decision on whether it would be played was to be made by four hours before faceoff, the Bruins said. Saturday night’s originally scheduled game between the Buffalo Sabres and Penguins in Pittsburgh was rescheduled for Tuesday night.

“We totally understand the situation and (are) respectful of that,” Penguins general manager Ray Shero said. “Hopefully, (we) have a chance to play tomorrow if that’s the case, but, again, the safety of the people of Boston, the city of Boston is most important for everybody.”