The assailant behind Wednesday’s attacks near the British Parliament has been identified as Khalid Masood, a 52-year-old resident of Central England’s West Midlands. The police said Masood had a number of aliases but was not part of any current investigation, AP reported. “There was no prior intelligence about his intent to mount a terrorist attack.”

Earlier in the day, the Islamic State group had claimed responsibility for the attacks, saying one of its “soldiers” had carried it out, AFP reported. Its affiliated news agency Aamaq said the assailant had “carried out the operation in response to calls for targeting citizens of the [US-led] coalition” fighting the extremist group in West Asia.

Prime Minister Theresa May had said that the assailant Britain-born and had been investigated for violent extremism a couple of years ago. She made the statement in the House of Commons after the London Metropolitan Police arrested seven suspects during raids in connection with the incidents. The police said Masood had been arrested previously for assault, possession of offensive weapons and disruption of public order.

Officials confirmed that the toll from the incidents was four – two civilians, police officer Keith Palmer and the assailant. Earlier, media reports had said that five people had been killed. On Twitter, the police said they had no explicit information about any future attacks.

London’s Parliament, the Metropolitan Police, government agencies and people across the country observed a minute’s silence to “honour the lives of the victims” at 9.33 am (UK time) on Thursday. London Mayor Sadiq Khan has urged people to join a 6 pm gathering at Trafalgar Square in solidarity with the victims and to “stand against terrorism”.

More than 40 people were injured during Wednesday’s attacks. The assailant, who had tried to enter the Parliament, was eventually shot dead by security forces. But he had managed to kill and injure several people on Westminster Bridge when he drove a car along a pavement while heading to the Parliament building.

The Metropolitan Police have urged the media to avoid disclosing details about the attacker as they are at a “sensitive stage of the investigation”. May had condemned the incident and called it “sick and depraved”.

Meanwhile, United States President’s son Donald Trump Jr drew criticism for tweeting a September 2016 article, which had quoted Khan as saying that terror vigilance had become “part and parcel” of life in a global city. His post was accompanied by a tweet that said, “You have to be kidding me?!” The US president’s son was rebuked online for implying that Khan had made the statements after the attack.

The attacks were similar to several others carried out in other European cities by the Islamic State group. On December 20, at least 12 people were killed and several others injured after a man drove a truck into a crowded Christmas market in Berlin. In July 2016, a truck driver had driven into a crowded street in France’s Nice, killing 84 people on Bastille Day. Both attacks were claimed by the West Asian extremist group.

Important numbers:

Police casualty bureau: 0800 056 0944 or 0207 158 0010.