QUETTA, Pakistan (AP) — A roadside bombing in a remote area in southwestern Pakistan, close to the border with Iran, struck a patrol vehicle on Friday, killing six soldiers, including an army major, the military said.

A statement from the military said the attack happened as the troops, assigned to look for smuggling routes and militants, were returning to camp from a mountainous border district of Baluchistan province.

No group immediately claimed responsibility for the bombing in the Keck district, but such attacks are common across Baluchistan and in its capital, Quetta.

The province has for years been the scene of a low-level insurgency by separatists who complain of discrimination and demand a fairer share of the province’s resources and wealth. Militants also have a presence in the province.