The Manchester Arena bombing was an Islamist terror attack in Manchester, United Kingdom. On 22 May 2017 a shrapnel-laden homemade bomb was detonated as people were leaving Manchester Arena following a concert by the American singer Ariana Grande. Twenty-three people were killed, including the attacker, and over 500 were injured.

After initial suspicions of a terrorist network, police later said they believed the bomber, Salman Ramadan Abedi, had largely acted alone but that others had been aware of his plans.