ISIL media claimed responsibility for a suicide bombing at a Shia mosque in Kuwait which killed 27 people and injured hundreds yesterday morning.
he attack, when the Al-Imam al-Sadeq Mosque was packed with thousands of worshippers during Friday prayers, was the worst terrorist incident in a Gulf state for more than 30 years.
A young man walked into the mosque and detonated an explosive belt strapped to his body.
"It was obvious from the suicide bomber's body that he was young," Khalil al-Salih, a Kuwaiti MP who was present, said. "He walked into the prayer hall during sujood (the kneeling in prayer). He looked in his 20s. I saw him with my own eyes. The explosion was really hard. The ceiling and wall were destroyed."
Shortly after the attack, claims of responsibility surfaced on social media.
A statement appeared purporting to be from "Wilayat Najd" of Islamic State of Iraq and the Levant (Isil) - Najd Province being in neighbouring Saudi Arabia.
It said the attack on the "rejectionists" - a sectarian term used by hardline Sunni groups for Shia - was because they were spreading their teachings in Kuwait. It called the mosque "a temple of the apostates". The country is majority Sunni but has a large Shia minority.
The statement gave the attacker's name as Abu Suleiman al-Muwahhid, though as that means "the monotheist father of Suleiman" it is more of a jihadist statement, since jihadists also complain of non-Sunni sects worshipping false gods.
Wilayat Najd is a relatively new branch of the Isil franchise. Saudi Arabia thought it had been relatively successful in preventing jihadist attacks at home in recent years, despite a large number of Saudis travelling to Syria and Iraq to fight with Isil and al-Qa'ida.
Last month, it carried out two suicide bombings at Shia mosques in al-Qudaih and Dammam in eastern Saudi Arabia, killing 21 and four people respectively.
Kuwait had increased security in response to those attacks. The country has a history of lower sectarian friction between Sunni and Shia than its neighbours, with most political conflict setting Islamists and democrats at odds with the ruling family. Soon after Friday's attack, Kuwait's ruler, Emir Sabah Al-Ahmad Al-Sabah, who is in his mid-80s, visited the bombed mosque. The Cabinet convened an emergency session in the afternoon. Arab leaders from across the Gulf rushed to condemn the attack.
But the attack also drew criticism from some Kuwaitis, who said the country's leaders should have been more pro-active in protecting Shiites.
Jasim al-Awadh, who rushed to the mosque to try and help with the wounded, said the government should have increased security measures around Shiite places of worship in Kuwait after the attacks in Saudi Arabia. He said the government turns a blind eye to Sunni extremists in the country.
Saudi Arabia and other petro-powerhouses in the Gulf have for years allowed a flow of private cash to Sunni rebels in Syria fighting to topple President Bashar Assad, who is backed by Shiite powerhouse Iran. When Isil began taking over large swaths of territory in Iraq and Syria, Gulf nations feared its extremism could be a threat to them as well, and began clamping down on fundraising as well as calls for jihad.
"I feel angry," Kuwaiti rights activist Ebtehal al-Khateeb said. "We want a complete approach and solution. There have to be serious changes in the region, not just in Kuwait."
Gulf officials warn that Isil is trying to provoke a reaction from Shiites, which could in turn destabilise or even upend the rule of the Mideast's Western-allied monarchies.
Attacks were 'signposted' by Isil
Earlier this week Islamic State of Iraq and the Levant (Isil) jihadists threatened "a calamity for kuffars" over the fasting month of Ramadan, at the same time releasing a gruesome new video of unorthodox execution methods.
The chief propagandist for Isil, Abu Mohammed al-Adnani, released the audio tape of his Ramadan message.
In it, he says that Haditha - west of Ramadi - will be the next town in Iraq to fall under Isil's sway, and incites more attacks by its followers worldwide.
The attacks should be on "kuffars" (infidels), "Crusaders, Shias and Apostates", he says.
"Be keen to conquer in this holy month and to become exposed to martyrdom," he says. The group is under pressure in north-east Syria, where Kurdish forces have pushed it back to around 30 miles north of its de facto capital, Raqqa, but has expanded elsewhere, including in Ramadi.