Saudi Arabia's Interior Ministry says that three of the four attackers who launched a deadly assault on a security patrol near the Iraqi border this week were Saudi nationals.

Ministry spokesman Mansour al-Turki published the names of the three in a statement on Friday. He says they had in their possession grenades, pistols, rifles, tracking devices and significant sums of money in U.S., Syrian, Iraqi and Saudi currencies.

Al-Turki says authorities have yet to confirm the fourth gunman's identity. All four gunmen died in Monday's attack, which killed three border guards.

No group has so far claimed responsibility for the attack, the first deadly assault on Saudi border guards near Iraq since the kingdom joined U.S.-led airstrikes against the Islamic State group, which controls parts of Syria and Iraq.