Two 'significant arrests' linked to London attack

The UK’s top anti-terrorism officer Mark Rowley said Friday that nine people were in police custody after "significant arrests" overnight in central and northern England. One woman detained earlier was released on bail.

Authorities say 52-year-old Khalid Masood carried out Wednesday's attack on Westminster, which killed four people and wounded dozens more.

Rowley told a press conference the man's birth name was Adrian Russell Ajao and appealed to anyone with information about him to come forward.

"There might be people out there who did have concerns about Masood but did not feel comfortable for whatever reason in passing those concerns to us," he said.

Police probe motivation

Rowley told reporters police were trying to work out what the attacker's motive was, and whether other individuals had "encouraged, supported or directed him."

The self-styled "Islamic State" group claimed responsibility for the attack on Thursday, saying Masood was one of its "soldiers."

Police have carried out more than a dozen searches and seized some 2,700 items since the attack, including "massive amounts of computer data," Rowley added.

Two people in critical condition

Masood plowed a car into pedestrians walking along the busy Westminster Bridge on Wednesday afternoon, killing three and injuring 50 before fatally stabbing a policeman outside the parliament building. He was then shot dead by another officer.

The death toll rose to four late Thursday after a 75-year-old man identified as Leslie Rhodes died of his injuries in hospital. Two people remain in a critical condition, Rowley said, with a number of others still receiving treatment for serious injuries. 

Masood, a Muslim-convert who used a number of aliases, was born in Kent, southeastern England. Although he had shown up on the intelligence radar in previous anti-terrorism investigations, he was considered to pose little threat.

nm/kms (AFP, AP, Reuters)