“Sixteen border guards, including a captain, were killed and four wounded in an attack targeting their headquarters in Al-Walid, near the Syrian border,” Faleh al-Issawi, deputy head of Anbar provincial council, told AFP.
He said the attack occurred at around 6:00 am (0300 GMT).
A commander in the Iraqi border force and a police major confirmed the death toll.
Despite the attack, “Al-Walid is still in the hands of Iraqi forces,” the major said.
The crossing is one of the country’s most remote outposts and lies 500 kilometres (310 miles) west of Baghdad near the westernmost point in Anbar province where the borders of Iraq, Syria and Jordan meet.
Jihadist fighters briefly held Al-Walid border crossing on June 23 but it has remained in government hands since.
Parts of the vast Anbar province, which also borders Saudi Arabia, have been out of government control since the start of the year, months before IS launched a major offensive across Iraq in June.
Government forces backed by US-led airstrikes, Kurdish forces, Sunni tribal fighters and Shiite militiamen have in recent weeks gradually clawed back some of the land lost since June.
But IS fighters have held their ground in Anbar and tried to tighten their grip on the province by attacking government positions and buildings in its capital Ramadi.
In a separate incident in the city of Tuz Khurmatu, about 160 kilometres (100 miles) north of Baghdad, at least four people were killed and seven wounded in a bomb explosion Monday.
Mayor Shellal Abdul said the blast in the centre of the city targeted people who had been displaced from a nearby village.
A doctor confirmed the toll. -AFP