Seven people have been arrested and six properties have been raided across the country in connection with the attack outside Westminster the Metropolitan Police’s senior anti-terror officer has confirmed.

Mark Rowley said the arrests and raids took place in London, Birmingham and elsewhere in the UK.

In Birmingham armed police were seen as they carried out a late-night raid in Hagley Road in the Chad Valley area of the city.

West Midlands Police referred inquiries about the operation on Hagley Road to the Metropolitan Police, who at the time refused to say whether it was connected with Wednesday's attack in Westminster.

A witness who works close to the raided property said: "The man from London lived here."

Officers stormed a second-floor flat above a row of shops on Hagley Road at around 11pm, the witness said.

He added: "They came and arrested three men."

One of the flat's windows was covered in cardboard, with non-uniformed officers spotted taking pieces of equipment into the property.

As he was describing the events, the witness was interrupted by a police officer, who had been guarding the scene.

He had his details taken and was convinced to go to a police station with another officer.

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Four people, including officer Keith Palmer and the attacker, were killed in the attack and upwards of 40 people were injured in Wednesday's attack.

This is a revised death toll as police said five people had been killed last night.

It has also been revealed that 29 individuals are being treated, seven of whom are in a critical condition.

Defence Secretary Michael Fallon has said the working assumption is that the Westminster attack is linked to Islamic terrorism.

More to follow