Less than 24 hours after new terror attacks in London, Ariana Grande's benefit concert for Manchester, England, is going forward as scheduled.
He added that the suspects were killed within eight minutes of the first call to police warning them of the attacks.
It is the second reported terror attack in London this year.
Three men then left the vehicle and began to stab people, including a British Transport Police Officer.
Police said in March that 52-year-old Khalid Masood drove a auto into pedestrians on the Westminster Bridge, killing four people before fatally stabbing a police officer.
Prime Minister Theresa May confirmed the attack "is being treated as a potential act of terrorism" and said her thoughts were with "those who are caught up in these awful events".
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The attackers "had no clue what they were doing".
He said: "I saw that man with a knife in his hand and after that a man started screaming so I knew something wrong was happening".
More than 30 people were injured in the attack, according to the London Ambulance Service.
It is the third terrorist atrocity in Britain in less than three months after the Westminster and Manchester attacks in March and May.
The father of Lily Harrison, eight, who has a bruised lung and a shrapnel wound following the suicide bombing outside Grande's Manchester Arena concert on 22 May (17), told BBC Breakfast on Saturday that he feared his daughter was dead after she lost consciousness. May's office said she would chair a meeting of the government's COBRA emergency committee on Sunday.
"I'd like to remind people that the threat level remains at severe, which means an attack is highly likely".
Praising Ariana Grande for organising the huge benefit, she went on: "And I think Ariana has proved that by putting this together and allowing us to be a part of it".