By Beth Germano

CAMBRIDGE (CBS/AP) — Officials say power has been restored in Cambridge, just outside Boston, after a about a two-hour outage delayed commuters and affected the campuses of MIT and Harvard University.

NStar utility spokesman Mike Durand said about 17,000 customers were affected at the height of the Thursday outage, which was related to a transmission line.

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Harvard canceled an early evening forum featuring top officials of the Obama and Romney campaigns. University police said the entire campus had been without power, and officers assisted a few people stuck in elevators.

A spokeswoman for the Massachusetts Institute of Technology said people also were rescued from elevators there but critical services had backup power.

Traffic was snarled, and transit authority spokesman Joe Pesaturo says the area’s Red line was experiencing delays.

It was lights out at a liquor store on Massachusetts Avenue. “It was absolutely sudden. All we heard was a bunch of beeping in the store,” said manager Joe D’Agostino.

He faced the prospect of closing for the night when business should be booming. “We probably lost anywhere from 1,500 to $2,000.”

It was the height of food prep at the Plough and Stars restaurant, getting ready for the dinner rush, when the power went out. Owner Jennifer Lockwood said she worried immediately about the possibility of looting.

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There were business and safety concerns as pedestrians crowded the sidewalks in the dark, some using cell phone lights as their guide. “It’s a little surreal. You don’t see it this dark and quiet everyday near Central Square,” said Jarrod Trainque.

WBZ-TV’s Jonathan Elias reports

Intersections without traffic lights were manned by police to control cars and crowds of commuters. Gridlock made it tough for emergency crews to answer calls around the city.

The problem with the transmission line happened too suddenly. “Everything went dark and I lost all my work,” said Annie Hard who was at the computer at Harvard Business School. “I’m not sure what I’m going to do tomorrow morning. It flicked and then it was gone.”

NStar says they had one of two transmission lines out of service for upgrade work when the second line tripped causing the outage. According to the utility, they were able to isolate what they believed to be the problem and restore power, but an investigation is now underway.

WBZ-TV’s Beth Germano contributed to this report

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(TM and © Copyright 2011 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2011 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

Beth Germano