On 26 June 2015, a suicide bomber detonated an explosive device inside the Imam Ja'far as-Sadiq Mosque, a Shia mosque in the Sawabir district of Kuwait City, during crowded Friday prayers held during Ramadan. More than 2,000 people were praying at the time, and a witness who was a member of parliament described the bomber entering the last row of worshippers before detonating the device, which severely damaged the building's ceiling and walls. Twenty-seven people were killed — including 19 Kuwaitis, three Iranians, two Indians, one Saudi, one Pakistani, and one Bedoon — and 227 were wounded, with 40 still hospitalized two days later.
The Islamic State of Iraq and the Levant (ISIL) claimed responsibility, identifying the bomber as Abu Suleiman al-Muwahhid and describing the mosque as a "temple of the rejectionists." Kuwaiti authorities later identified the bomber as Fahd Suleiman al-Qabba, a Saudi citizen born in 1992, who had entered Kuwait by commercial flight the day of the attack. Investigators said the attackers had been instructed roughly 20 days earlier to carry out an operation to "shake Kuwait up," and that explosives were delivered by associates from Saudi Arabia. Within days, Kuwaiti authorities arrested several people, including the driver who transported the bomber to the mosque and the owner of the house where the bomber had stayed. Saudi authorities separately arrested three brothers suspected of involvement.
On 14 July 2015, the public prosecutor charged 29 people, seeking the death penalty for 11. After roughly ten mostly public court sessions, the Criminal Court ruled on 14 September 2015 that 15 of the 29 defendants were guilty, with seven receiving death sentences, five of them in absentia. Adel Eidan — who admitted driving the bomber to the mosque and brought explosives from Saudi associates, claiming he wanted to bomb the mosque itself but not kill people — had his death sentence upheld on appeal and by the Cassation Court, making him the only defendant present in Kuwait facing execution; the sentence of an ISIS leader in Kuwait, Fahad Muharib, was reduced to 15 years on appeal. On 27 July 2023, Eidan, described as a stateless man involved in the attack's logistics, was executed by hanging at Kuwait's Central Prison alongside a group of other people.
The Emir, Sheikh Sabah al-Sabah, arrived at the scene shortly after the bombing and later ordered the mosque's reconstruction; it reopened in June 2016. Funeral processions drew large crowds, including at least 35,000 mourners at Ja'fari Cemetery. A subsequent lawsuit accused the Kuwaiti government of negligence in failing to protect the mosque; an appeals court found the government liable, but Kuwait's Supreme Court later ruled the government not guilty, citing "sufficient measures" taken. The bombing occurred alongside two other Islamist attacks the same day, in France and Tunisia, and an attack in Somalia, following an ISIS call to attack during Ramadan, though no definitive link between the attacks was established.