Police patrols have been stepped up on trains and at rail stations across the country after the latest suspected terror attack outside the Houses of Parliament in London.

A driver was arrested on suspicion of terror offences after a car collided with cyclists and pedestrians before crashing into security barriers just before 7.40am on Tuesday.

The man, in his late 20s, is being held in custody at a south London police station.

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Confirming that train patrols would be stepped up, Superintendent Chris Horton, from British Transport Police, said: “We know incidents such as this are likely to cause concern, so our officers will be highly visible both on board trains and at stations.

“We are there to reassure the travelling public so please don’t be alarmed if you see our officers, including firearms officers, on your journey.”

WATCH: Terror suspect arrested as car crashes into Parliament security barriers

Police in Scotland, meanwhile, said they were not aware of any imminent terrorist threat north of the Border.

However, officers have urged members of the public to be vigilant.

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Detective Chief Superintendent Gerry McLean, Police Scotland Head of Organised Crime and Counter Terrorism, said: “Following this morning’s incident at the Houses of Parliament, Police Scotland has been monitoring the ongoing situation and liaising with counter-terrorism colleagues across the United Kingdom.

“There is absolutely no intelligence or assessment to suggest Scotland is going to be the target of a terrorist attack.

"As per the statement from the Metropolitan Police Service in London, we do not believe there to be a wider risk to the public in the UK.”

He added: “As ever, we encourage the public to remain alert, not alarmed, but to be vigilant and report anything suspicious to the police as soon as possible.”