What we know about the Manchester attacker's bomb

Manchester suicide bomber Salem Abedi used a powerful explosive device that was painstakingly assembled -- likely with assistance -- for his deadly attack on a pop concert, according to officials and experts.The British-born 22-year-old of Libyan descent detonated the blast on Monday evening, killing 22 people outside a packed Manchester Arena after a show by US pop star Ariana Grande.Ten men are now in custody in connection with the attack, including Abedi's brother and father in Libya.