Police have arrested two men in the heart of London just after midnight on Thursday on suspicion of plotting terrorist activity.
The suspects, who have not been named, were spotted behaving suspiciously in a car in Westminster and were pulled over by armed police on Pall Mall—the road that links Buckingham Palace to Trafalgar Square.
The suspects are both aged 34, according to the police.
“Every day, police officers are on patrol across the capital, watching for suspicious behaviour and stopping people they suspect may be involved in criminality," Commander Richard Smith, head of the Met Police Counter Terrorism Command, said in a statement.
“The public can help us continue to keep London safe by being vigilant and reporting any suspicious behaviour to police."
The arrests come just a week after the terrorist threat level in the UK was bumped up to the second-highest tier.
Smith said that the raised threat level was a precautionary measure in response to recent events in France and Austria.
"I would like to emphasise that the public should be alert but not alarmed," he said.
In an unrelated incident, London police last night arrested a man on suspicion of arson and other offenses after he drove his car into a police station door, then poured petrol on the road and set it on fire.
Met Police Commander Ade Adelekan said in a statement: “This appears to have been an isolated incident and does not seem to be terror-related. I am satisfied that there is no wider risk to the community.”
“Local officers will continue to carry out enquiries, but at this stage we are not looking for anybody else,” Adelekan added.
“I also acknowledge the brave actions of local officers who confronted and arrested the suspect in a dangerous and challenging situation.”

As the flames erupt, a police car pulls up.
Seconds later, a member of the public appears to grapple him and throw him to the ground, just before two police officers pin him down.