Saudi authorities arrest 13 suspects day after IS-claimed attack

Saudi authorities arrested 13 "terrorist" suspects Monday a day after an attack claimed by the Islamic State group on a security services base north of the capital, state media said.

Saudi Press Agency, quoting a state security spokesman, said the arrests were part of an investigation by authorities into "terrorist" activities.

Authorities, it said, arrested 13 "terrorist" suspects who were "preparing to carry out criminal activities against the security of the country",  the agency said.

But it did not say if the arrests were linked to Sunday's attack or where they took place.

SPA said four men who attacked Sunday a security services base in the province of Zulfi, northwest of the capital Riyadh, were all Saudi citizens.

The men were killed by security forces as they stormed the building, and three Saudi policemen were wounded in the attack.

IS claimed responsibility for Sunday's assault.

The kingdom has seen numerous attacks in recent years by militants, including Al-Qaeda and IS, against security forces.

It has also seen clashes between Shia militants and security forces in the eastern provinces.

Sunday's attack took place in a majority Sunni region.

An estimated 10-15 percent of the ultra-conservative kingdom's 32 million population are Shia, although no official figures exist.