A suicide bomber attacked a mosque in Aseer, in south-western Saudi Arabia, on Thursday, killing no fewer than 17 members of the security forces, local media have reported.
There were many injured in the blast, which appeared to target a mosque often frequented by the security forces in Abha city, the capital of Aseer province, near the border with Yemen.
The attack is the latest in a spate of bombings in the country, many targeting members of the Shiite minority.
In May, the Islamic State extremist group claimed an attack against a Shiite mosque which killed 20 people in the eastern Qatif province.
Saudi Arabia recently initiated a crackdown against the extremist group, arresting hundreds of alleged sympathisers.