PORTSMOUTH, N.H. (WBZ) ―

A Greyhound bus heading for New York City is being blocked by police
and fire officials in downtown Portsmouth, New Hampshire, after a
report of a possible bomb on board.

17 passengers and a driver were on the bus when it stopped around 11:30 a.m.

About two hours later, they left the bus one by one -- separated by a couple of minutes each -- and carried no purses or bags.

Most held their hands up as they passed officers with their weapons drawn.

The passengers were screened individually when they got off the bus --
much like an airport security check -- and were to be taken to the
Portsmouth police station.

No one appeared to be hurt.

As of 3:30 p.m., all but one passenger was off the bus. Police would
not confirm or deny if the man is a suspect. They would only call him
"the last person on the bus."

According to WBZ's Peg Rusconi, the man on the bus is in communication
with officers via cell phone. Officials are working on bringing in an
interpreter to help talk with the man on the bus.

The bus was heading from Bangor, Maine to New York City with stops in Portland, Portsmouth and Boston along the way.

Police say a call came in from someone concerned about a device they
had seen on the bus, but they have not found any device at this point.

Earlier in the day, sources told WBZ's Karen Anderson that a man on the
bus was talking on a cell phone and a woman apparently heard him say
something about "a bomb is on the bus."

The woman told the bus driver, who then pretended there was a
mechanical problem with the bus and pulled over in Portsmouth. The
driver then called police.

Officers shut down streets and evacuated businesses, including a Hilton hotel in the busy downtown area.

Two SWAT teams and the FBI are also on the scene.

Investigators were not calling it a hostage situation.

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Associated Press contributed to this report.)..