BOSTON -- A report of a suspicious package at Boston's South Station rail terminal prompted the evacuation of the entire station late Thursday morning. Police also cordoned off surrounding streets.

The station was declared safe and reopened after it was determined that a ticking sound coming from a piece of luggage was a cassette player that had been left on inside the bag, MBTA spokesman Joe Pesatauro said. He said a couple that was traveling went to retrieve their luggage and thought it looked as if it had been tampered with. They said they heard the ticking sound and notified authorities.

"The bags were X-rayed twice and they were deemed to not pose a threat. It turned out that the sound was coming from a cassette player within one of the bags," Pesatauro said.

MBTA police and Boston fire and police crews secured the area and determined the station to be safe just before noon, but not before the closure of streets around the station snarled traffic leading into the downtown area. No injuries were reported.

According to police, a call on a suspicious package was received about 10:50 a.m., primarily affecting commuter rail service into South Station. Officials said service on the Red Line was not affected and it was running on schedule.

North Station was not affected by the shut down.

Massachusetts Bay Transportation Authority rail and bus lines operate out of South Station, as do Amtrak trains.