A Liberal Democrat activist has said party activists were detained in their office by armed police investigating an incident outside last night.
The Newcastle Falcons rugby ground at Kingston Park to the north of the city was sealed off after loud bangs were heard.
A man with a handgun walked into a bar at the rugby ground and fired two shots without injuring anyone, a Liberal Democrat source said. The gunman fled.
Newcastle North Liberal Democrat organiser James Kenyon said he was unable to leave the party's Newcastle headquarters because of the situation.
He said: “There is a police BMW 4x4 outside and a Volvo police car and the police helicopter is going backwards and forwards.
“At the bottom of the stairs outside is a police officer with a helmet carrying a machine gun.
“He saw me trying to come down the stairs and he looked unhappy so I rather hastily made my way back in.”
With Mr Kenyon were city councillor Peter Allen and wealthy businessman Sir Ian Wrigglesworth. He said: “We hope the situation will be resolved soon so we can get to the count.”
Northumbria Police said it was not able to comment.