The two gunmen were trying to "infiltrate" a police station parking area in the western Taif province to carry out a "terrorist act", the ministry said in a statement on the official SPA news agency.
Saudi policeman shot dead after Makkah raid: ministry
As they realised that they were being monitored, the men opened machinegun fire at police and fled in a waiting vehicle. Chased by security forces, they abandoned the vehicle and fled into a residential area, the statement said. An exchange of fire left policeman Saeed al-Harithi dead, it said.
Security forces surrounded the area and were searching for the suspects, it said, adding that a suicide vest and nine improvised explosives were found.
The past week has seen a rise in such incidents in the kingdom, where the Islamic State group has previously claimed bombings and other attacks targeting security forces.
4 dead in Saudi raid on 'terror' cell near Makkah
On Thursday, a Saudi police officer was shot dead after four suspected extremists died during a raid in the area between Taif and the region of Makkah, home to Islam's holiest sites.
IS leader Abu Bakr al-Baghdadi has called Saudi Arabia's rulers "apostate tyrants" and called on Saudis to rise up against them.
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