Saudi authorities have arrested two suspects in the terrorist blast that hit Kuwait's Al-Imam Al-Sadiq Mosque on 26 June, the Kuwaiti Interior Ministry said in a statement on Tuesday.
It added that the step was based on information coordination with the Kuwaiti security authorities.
The suicide blast that hit the mosque in downtown Kuwait city during Friday noon prayer claimed the lives of 26 people and left 227 others wounded.
The two suspects had delivered the explosives to Abdul-Rahman Sabah Aidan who drove the suicide bomber to Al-Imam Al-Sadiq Mosque, the ministry said.
According to the statement, investigations and analyses have shown that the explosives used in Kuwait's blast were the same kind used in the terrorist blasts that targeted two Saudi mosques in May.
The two suspects are Saudi brothers, Majid Abdullah Mohammad Al-Zahrani and Mohammad Abdullah Mohammad Al-Zahrani. A third was arrested in Kuwait and handed over to the Saudi authorities, while a fourth is in Syria "with the Islamic State in Iraq and the Levant (ISIL)."
They had entered Kuwait on Thursday 25 June through Al-Nowaiseb border outlet where they delivered the explosives in an ice box to Aidan, then leaving immediately. Aidan later handed the explosive materials to the bomber, Fahad Al?Gabbaa a day later.
According to Saudi-Kuwaiti security information, Majid Al-Zahrani was detained in Al-Taif, and Mohammad Al-Zahrani was caught in Al-Khafji after fire exchange with the Saudi security. Two security men were injured.
The Saudi authorities also found a Honda Accord, the same car suspects used to transport explosives to Kuwait.