An explosion at a Shiite mosque in Kuwait City after Friday prayers left 27 dead and more than 200 injured, according to news agent AFP.
The toll in the attack, carried out in the Muslim holy fasting month of Ramadan, is one of the largest in Kuwait's history.
The official Kuwait News Agency reported that a blast hit the Imam Sadiq Mosque, which is located in the neighborhood of al-Sawabir, a residential and shopping district of Kuwait City. The police formed a cordon around the mosque's complex immediately after the explosion and banning people from entering it.
The Islamic State claimed responsibility for the suicide attack, according a statement posted on social media.
The IS-affiliated group in Saudi Arabia, calling itself Najd Province, said militant Abu Suleiman al-Muwahhid bombed the mosque which it claimed was spreading Shiite teachings among Sunni Muslims.
IS, a radical Sunni group, considers Shiites to be heretics.
The Najd Province group has claimed similar bombings at Shiite mosques in Saudi Arabia in recent weeks.
The statement identified the bomber as Abu Suleiman al-Muwahed. It said the target was a "temple of the rejectionists" -- a term used by the Islamist militant group to refer to Shiite Muslims.
Friday midday prayers are the most crowded of the week, and attendance increases during the holy Muslim month of Ramzan, which started last week.
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