UK Parliament terror attack: Seven arrests after raid on six addresses; toll lowered to three

Three people were killed and about 40 injured on Wednesday when a car ploughed into pedestrians close to Britain`s Parliament.

London: The British Police has arrested seven people in connection with Wednesday`s terror attack at the British Parliament.

The arrests took place in London and Birmingham. 

"We have searched six addresses and made seven arrests," Acting Deputy Commissioner and Head of Counter Terrorism Mark Rowley told reporters in London.

Rowley added that the latest figures were that there were four dead including the attacker and 29 people being treated in hospital, seven of whom were in a critical condition.

Police had said late on Wednesday that the death toll was five.

Rowley said police had searched addresses in London, Birmingham and other parts of the country in their investigation.

"It is still our belief ... that this attacker acted alone and was inspired by international terrorism. At this stage we have no specific information about further threats to the public," Rowley said.

He said there was a mix of nationalities among the dead but gave no details. The victims were a policeman who was stabbed and two members of the public, a woman in her mid-40s and a man in his mid-50s.

The fourth dead was the assailant.

Police believe they know the identity of the attacker but have not named him.

The attack on Wednesday started when the assailant sped across Westminster Bridge in a car, ramming pedestrians along the way. He then ran towards Parliament and stabbed the policeman before he was shot.

Westminster Bridge remained cordoned off with a strong police presence. The nearby Westminster underground train station, normally a busy hub in the morning rush hour, was not accessible from street level as it was within the cordon.

Prime Minister Theresa May had described the attack as "sick and depraved" in a defiant address in which she affirmed Parliament would meet as normal on Thursday.