Wearing women’s clothing as a disguise, the suicide bomber – identified as 20-year-old Khaled al-Wahbi al-Shemari – detonated the explosive belt he was wearing at entrance of the Al-Anoud mosque, the Saudi interior ministry said.

The interior ministry also said that it has identified 16 other people linked with that attack and an earlier bombing on a mosque in the eastern al-Qatif governorate, which killed 21.

The Islamic State of Iraq and Syria (ISIS) militant group claimed both attacks.

The ministry is offering $270,000 to whoever provides information leading to the arrest of the suspects and $1.9 million to anyone who helps thwart a militant attack.