Meanwhile, on Monday, militants carried out three separate suicide bomb attacks across Saudi Arabia, including an attack in the holy city of Medina that killed four security officers near the mosque where the Prophet Muhammad is believed to be buried. The mosque is one of the holiest sites for Muslims worldwide. Another separate attack near the U.S. Consulate in the Saudi city of Jeddah wounded two security officers. No one has yet claimed responsibility for Monday’s attacks. The string of deadly attacks comes only days after militants attacked the main airport in Istanbul, Turkey, on Tuesday, killing 42 people. The airport is the 11th busiest in the world.