London attack: Queen Elizabeth honours 'hero' minister

Officers have seized 2,700 items, including computer data, and have had contact with 3,500 witnesses to the attack, many of them of different nationalities, Rowley said.

Scotland Yard has said that Khalid Masood, the man behind the brutal attack on Westminster, London on Wednesday, acted alone, according to the BBC.

Of the 29 people taken to hospital, seven are said to be in a critical condition.

A report dating back to November 2000 shows he was sentenced to two years in prison for slashing the face of a cafe owner in a village in southern England where he lived with his family.

A total of 11 people were held on suspicion of preparation of terrorist attacks in the wake of the attack.

It was the deadliest in Britain since four homegrown suicide bombers killed 52 people on the city's transport system in July 2005.

A 39-year-old woman arrested in east London has been released on bail until late March.

Along with the man arrested Sunday, a 58-year-old man detained in Birmingham several days ago remains in custody in the case.

Khalid Masood - a convert to Islam who spent significant time in Saudi Arabia and was identified as a possible jihadist - was shot dead after plowing his vehicle through pedestrians, killing two and injuring dozens, on Westminster Bridge before stabbing and killing an officer outside the parliament.

Masood, who was born in Kent and is thought to have been living in the West Midlands, had previous convictions for violence.

British Prime Minister Theresa May's office says Tobias Ellwood has been named to the Privy Council, a committee of senior lawmakers, judges and others that advises the queen.

Masood was once investigated in relation to concerns about violent extremism by British authorities, but the Metropolitan Police have said he "was not the subject of any current investigations and there was no prior intelligence about his intent to mount a terrorist attack". ISIS did not name Masood in its statement released to Amaq, the news agency linked to the group. This phrasing has been used in the past by the group for attacks ISIS believes it helped inspire, he said.

Four other suspects remain in custody in connection with Wednesday's attack, which left five people dead, including the assailant, EFE news reported. "I'm confident that we are doing all that we can to keep our city safe, to keep Londoners safe and to keep visitors safe", he said.

Masood went on to stab Pc Keith Palmer to death in the grounds of the Houses of Parliament.

"The way that communities in London, and throughout the United Kingdom, have come together in the wake of this attack shows that we will not give into those who seek to breed discord and fear".

  • Zachary Reyes