BOSTON (AP) – The MBTA is apologizing for a power outage that brought the Boston subway system to a near screeching halt for a portion of the morning rush hour.

Transit officials say the outage began at 8:50 a.m. when a maintenance crew in South Boston tripped a breaker, cutting off one of two feeder cables that supply power to the subways. The second feeder was already off-line for preventative maintenance.

It took about 30 minutes before power was completely restored. In the meantime, some 60,000 passengers were stuck on trains and trolleys, many in darkened tunnels.

One Red Line train was evacuated, and passengers had to walk about 70 feet to reach the Shawmut Station.

With temperatures pushing 90 degrees, passengers were at least thankful that the air conditioning continued working on trains.