Saudi Arabia says two armed men, including one with a suicide vest, attacked a patrol of border guards near the kingdom's frontier with Iraq, killing two guards and wounding a third.

The Interior Ministry says the attack occurred at dawn Monday near Arar, the provincial capital of the Northern Borders Province, along the border with Iraq.

It describes the attackers as "terrorists" and says they opened fire on the patrol. The guards returned fire, killing one of the attackers. The other detonated his explosives and blew himself up.

No group immediately claimed responsibility for the attack.

Saudi Arabia has joined the U.S.-led alliance against Islamic State militants and is participating — along with Jordan, Bahrain and the United Arab Emirates — in airstrikes in Syria, with logistical support from Qatar.