Two men killed in a gunfight in southern Saudi Arabia were known Al-Qaeda militants who carried a store of explosives and four suicide vests for use in an "imminent" attack, the government said on Sunday.
Saudi authorities have arrested six Yemenis in the wake of the shootout in Jizan province on Tuesday, and are searching for more people believed involved in the planned attack, according to the interior ministry.
The ministry said the two men, along with a third, their driver who was captured after the gunfight, had snuck into the country from Yemen and were carrying RDX explosives, Kalashnikov assault rifles, grenades, pistols, and four suicide vests in their car when they were intercepted.
"They had infiltrated into Saudi territory from the border to undertake an imminent criminal act," the government said.
The two dead men had disguised themselves as women wearing conservative head-to-toe black abayas and suicide vests fully ready for use, according to the interior ministry.
Ministry spokesman General Mansur al-Turki said there were still no details available on the planned target or targets of the men.
"The investigation is still ongoing. There are more we are still looking for," he told AFP.
The two dead men, identified as Yousef al-Shehri and Raed al-Harbi, were both Saudis who were included on a list of 85 wanted alleged Al-Qaeda associates Riyadh handed over to Interpol earlier this year.
Turki said the men were clearly planning what could have been a major attack. Besides the two suicide vests they were wearing, there were two more in the car, one ready for use and another to be assembled.
One of the vests was packed with ball bearings as shrapnel.
"When this exploded, it could have hurt so many people," Turki said.
The gunfight broke out after police stopped the car at a highway checkpoint on the road north from Jizan to Abha.
One police officer was killed and another wounded in the battle.
The incident highlighted Saudi worries that the Yemen-based Al-Qaeda in the Arabian Peninsula (AQAP) was plotting more attacks against Saudi targets, four years after the government successfully put down a Qaeda campaign of bombings and assassinations with a severe crackdown and thousands of arrests.
On August 28, Prince Mohammed bin Nayef, the powerful deputy interior minister responsible for the kingdom's anti-terror fight, escaped a suicide bomb attack in his Jeddah palace.
A wanted Saudi member of AQAP, ostensibly turning himself in to the prince, detonated an explosive reportedly hidden in his rectum.
Aside from killing the bomber himself, however, no other serious injuries were reported in the incident.
That attack followed the arrest in Saudi Arabia earlier in August of 44 Al-Qaeda suspects, including one foreigner, and the discovery of arms caches used by the group.
Police found about 70 machine guns, as well as ammunition and 280 electronic detonation devices in Riyadh, and another 96 similar devices hidden in the desert in the Qassim region north of the capital.