Manchester on Friday marked the third anniversary of the terrorist attack which killed 22 people and injured hundreds. (Photos: Xinhua)

The attack happened when Salman Abedi detonated a bomb at the end of a concert by U.S. pop singer Ariana Grande on May 22, 2017.

People grieve at a memorial of the Manchester Arena attack in Manchester, Britain, May 22, 2020.

People grieve at a memorial of the Manchester Arena attack in Manchester, Britain, May 22, 2020.

People grieve at a memorial of the Manchester Arena attack in Manchester, Britain, May 22, 2020.

Peoplpe grieve at a memorial of the Manchester Arena attack in Manchester, Britain, May 22, 2020.