Saudi Arabia has arrested 19 people, including seven locals and 12 Pakistanis, in connection with three suicide bombings that took place across the country on July 4, including one near the prophet Mohammed's mosque in Medina.
The bomber who attacked the holy city of Medina was a 26-year-old with "drug abuse history," state-run Saudi Press Agency reported Friday. Four security officials were killed in the attack, which was widely condemned by Muslim leaders, including those from hardline groups.
Only the attackers were killed in the two other Monday bombings, which occurred in the mainly Shiite eastern city of Qatif and near the US consulate in the western city of Jeddah.
Observers have speculated that Islamic State might be behind the attacks.