Salman Abedi, a Manchester-born 22-year-old, blew himself up outside the stadium at the end of an Ariana Grande concert held there on Monday, local time.
As well as the 22 people killed, more than 120 were injured.
Five people have been arrested in the UK since Monday night, including Abedi's older brother, Ismael, who was detained in Chorlton, south Manchester, on Tuesday.
