Mark Rowley is deputy commissioner for London’s Metropolitan Police Service.
While he was registered in Dartford, Kent as Adrian Russell Elms at birth Masood was also known as Adrian Russell during his childhood.
“It is still our belief, which continues to be born out by our investigation, that this attacker acted alone and was inspired by global terrorism”, Rowley told reporters.
One person was arrested overnight in the West Midlands region of England, where several people had been detained earlier, and a second was taken into custody in the northwest of the country, he said.
The two women and four men were all arrested in the central England city of Birmingham, where attacker Khalid Masood recently lived. The dead include the police officer who was stabbed and the attacker who was shot by an officer.
On Thursday, ISIS claimed Masood was one of its “soldiers” in a statement released on its Aamaq news agency.
The revelation came as Met detectives continued to investigate whether Masood, who used a number of other aliases, acted alone or had accomplices.
On the eve of the attack that Prime Minister Theresa May cast as an attack on democracy, Masood spent his last night in a budget hotel in Brighton on the south coast where he ate a takeaway kebab, the Sun newspaper said.
Three other people died after Masood’s vehicle ploughed into them on Westminster Bridge: Spanish teacher Aysha Frade, 43; American tourist Kurt Cochran, 54; and retired window cleaner Leslie Rhodes, 75, who succumbed to his injuries late on Thursday.
The attacker mowed down pedestrians as he drove across the Westminister Bridge, hitting and injuring members of the public.
A Regina woman who was in London during the deadly attack on Wednesday said although the incident was scary, it’s important not to allow terrorist attacks “to start dividing society, breaking trust between populations and communities”.
The female victim was named by British media as Spanish teacher Aysha Frade, 43, a mother of two who was on her way to collect her children from school when she was killed.
“As a result of their co-operation and our enquiries, we are completely satisfied that they are not connected in any way to the terrorist attack in Westminster on Wednesday”, he said.
“I would like to put on record my gratitude to the journalists who having identified the dead terrorist soon after the attack have delayed publishing his details at my request to give us space to move on the necessary warrants, searches and arrests”. Experts said that the incident was the latest case of a growing threat of low-tech terrorism.
According to The Guardian, the attacker was born on Christmas Day 1964. In Parliament’s New Palace Yard, a blue police tent was erected over the spot where the stabbing and shooting occurred, and two forensic officers worked at a trestle table nearby.
Two pedestrians died in the attack – a woman in her 40s and a man in his 50s.