Hostage drama at Hillary Clinton's New Hampshire campaign office

An armed man has reportedly taken two campaign workers hostage at Hillary Clinton's New Hampshire campaign office.

American news outlets are reporting that a man walked into the office of the Democratic presidential candidate in Rochester, New Hampshire, and claimed to have a bomb with him.

"A young woman with a 6-month or 8-month-old infant came rushing into the store just in tears, and she said, 'You need to call 911. A man has just walked into the Clinton office, opened his coat and showed us a bomb strapped to his chest with duct tape,'" the WMUR-TV station quoted a woman called Lettie Tzikik as saying.

Armed police in the town have surrounded Clinton's building and evacuated the immediate area. Clinton is not in New Hampshire today, but is campaigning in Virginia.

It is not known how many campaign volunteers were in the office when the incident occurred.

U.S news networks are now reporting that reporters have witnessed one of the two hostages, a female, being escorted out of Hillary Clinton's office by a SWAT team member.

It has also been reported that the remaining one hostage may also have been released.

The armed man is described as in his 40s with salt and pepper hair, and was said to have demanded to speak to Hillary Clinton.

There were initially four adults and a six-month-old child in the office but two of the adults and the child were immediately allowed to leave the office.

The armed man at the centre of the Hillary Clinton bomb threat in Rochester, New Hampshire, is reportedly a local man with a history of mental illness.

U.S news networks say that the hostage taker, whose name has been given as Troy Stanley, told his son, Troy Stanley Jr., 'to watch the news today.'

One eyewitness told FOX News that Stanley had told people in the town he had 'a bug implanted in his head.'

The hostage taker remains holed up in side the Clinton office after releasing all of the hostages.