In this Wednesday, Sept. 9, 2015 photo, Muslim pilgrims circumambulate around the Kaaba, the cubic building at the Grand Mosque in the Muslim holy city of Mecca, Saudi Arabia. Thousands of Muslims from all over the world have arrived in Saudi Arabia for the annual hajj, or pilgrimage, to Mecca. Every Muslim is required to perform the hajj, or pilgrimage, to Mecca at least once in his or her lifetime if able to do so. (AP Photo/Amr Nabil)

ISIS Attacks In Saudi Arabia Test Security Of Hajj

So far, the extremist group’s presence in the kingdom appears to be in a low-level stage, but it has claimed four significant bombings since May, one of them in neighboring Kuwait.