George Galloway was left dazed and bruised today when an office worker hurled a rubber stress ball at his head.

The Respect Party MP was touring Central London in an open top bus ahead of this month’s elections when the stress relief toy, thrown from a first floor window, struck him on the side of the head.

The politician and reality television star was knocked off his feet by the rubbery missile, which aides described as hollow and slightly smaller than a tennis ball.

Kevin Ovenden, one of his advisors, said: “It hit George on the left side of his head, on the temple. He was momentarily dazed and because of the impact of the blow he lost his balance and hit the other side of his head on the side of the bus.

“There is a nasty bruise on the side of George’s head, but he will continue campaigning for the local elections.”

The ball is believed to have been thrown from an office block on Procter Street, Holborn shortly after 2pm.

Police have arrested a man, thought to work at a research company. He was being questioned by officers this evening.

A Scotland Yard spokeswoman said: “Officers from Camden borough attended the office block and have arrested a person in connection with the incident. That person is currently in custody at a north-west London police station.”

Mr Galloway, 53, MP for Bethnal Green and Bow, received medical treatment but was not taken to hospital.

He was travelling on his “battle bus” with his granddaughter and a team campaigning for the London Assembly elections when he was struck near the corner of Theobalds Road and Red Lion Square in Holborn.

Colleagues said he was "momentarily dazed" and a spokesman told the East London Advertiser: “It was a direct hit.”

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