A minute’s silence at was observed at the headquarters of the Metropolitan Police in London at 9.33 am on March 23, to honour the victims of the March 22 attack at Westminster.

Acting Met Police commissioner Craig Mackey spoke after the silence and paid tribute to PC Keith Palmer, who died in the attack.

At least four people, including a police officer and a suspect, were killed in Wednesday’s attack, the BBC reported. The suspect was shot dead by police in Westminster.