DUBAI, United Arab Emirates -- Authorities in Saudi Arabia say police have shot and killed two suspected Islamic State extremists in the capital, Riyadh.

The Interior Ministry says the two suspected militants opened fire Saturday on police after being surrounded in the capital's northern Yasmeen neighbourhood, forcing officers to return fire and kill them. It said one officer was slightly wounded.

The Interior Ministry published photos of explosive suicide vests, rifles and ammunition it said officers found. It also said material found inside the home the two men hid in suggests it was used to manufacture bombs.

Saudi Arabia has faced a series of attacks from a local Islamic State affiliate.

The militant threat in the kingdom is the most serious it has faced since an al Qaeda insurgency over a decade ago.