WASHINGTON, Dec 21: Police blocked off several city streets near the White House on Tuesday, bringing rush-hour traffic to a standstill after a "possible" hostage taking at a Rite Aid pharmacy.

At least 30 police cars surrounded the scene and six streets were closed to traffic and pedestrians as hundreds of workers were kept from their offices in below freezing temperatures.

Nine police officials in heavy body armour entered the store, weapons raised, after a handful of people - apparently hostages being released - left the building. Police spokesman Junis Fletcher said that police had responded to a report of a robbery and encountered a "possible hostage situation".

"There may be someone still inside," he said. One woman said she was in the store at the time of the hostage-taking, but did not see the gunman. "I was standing at the counter. ... I thought it was unusual because no one was there," she said.

She said she was told that a gunman had forced a woman into the photo lab area near the cash register. Then two police officers entered the store and said "Everybody get out", she added.

An armoured vehicle was parked in front of the store as police in body armour peered through the shop's windows and stood sentinel outside. The pharmacy is located one block from the headquarters of The Washington Post and only three blocks from the White House. -AFP