Two Pakistani coast guards were killed today when a bomb exploded under their vehicle, police officials said, in a town in the southwest which has been hit hard by years of separatist violence.

The blast, which also injured three coast guards, completely destroyed the vehicle during a patrol on the outskirts of Jewani town in Baluchistan province, the police officials said. No one has claimed responsibility for the explosion.

Jewani lies in Gwadar district, whose port is at one end of the proposed $46 billion China-Pakistan Economic Corridor stretching from the Arabian sea to China's Xinjiang region.

Separatist groups in Baluchistan, one of Pakistan's poorest provinces, have waged violent campaigns over the past decade, saying the Pakistani state has failed to develop the impoverished region and instead plundered its natural resources.

Much of the separatist violence over the past decade has targeted government personnel and security forces as well as non-Baluch ethnic groups.

Baluch activists say thousands of people have disappeared and there have been hundreds of extrajudicial killings in security force crackdowns.

The China-Pakistan Economic corridor offers Beijing a shorter and cheaper route for trade with the Middle East and Europe and could bring investment to the region, but poor security has raised doubts about the feasibility of the plan.

Last year gunmen stormed Jewani airport in Baluchistan, killing engineers and destroying radar systems