BOSTON — A malfunctioning signal outside Boston’s busiest commuter hub triggered massive delays Thursday for rail passengers with no immediate word on when the problem might be fixed.

Passengers on commuter rail trains from west and south of the city were forced to get off trains at stops before South Station and transfer to rapid transit lines or, in some cases, walk the remaining distance to their destination.

The signal is operated by Amtrak, which said track switches were being operated manually, significantly reducing the amount of trains that can arrive or depart from the station. Amtrak was also reporting delays of 30 minutes to 2 hours on some trains departing Boston for destinations on the Northeast Corridor such as New York, Philadelphia and Washington.

Massachusetts transportation officials said Amtrak had notified them that the problem would persist through the evening rush hour and gave no assurances that it would be corrected before the Friday morning commute.

“I’ve been ready to strangle somebody all day,” a frustrated Massachusetts Gov. Charlie Baker said during his monthly “Ask The Governor” segment on WGBH-FM. “I’m just waiting for somebody who looks like they deserve to be strangled.”