At least two NATO oil tankers were torched in Chaman in Pakistan's southwest province of Balochistan on Monday morning, reported local media.

The incident happened when some unknown gunmen attacked the NATO oil tankers and set them on fire.

Police sources said they had arrived at the scene shortly after the attack was reported and fire brigades are now trying to put off the fire.

No people were killed in the attack, said police sources, adding the attackers had run away.

So far no organizations have claimed responsibility for the attack.

This is at least the fourth attack targeted at the NATO supply convoy in Pakistan since this month.

On June 8, terrorists attacked a NATO supply convoy at a parking lot near Islamabad and over 60 NATO supply trucks, mostly oil tanker carriers, were destroyed and about eight people died in the attack.

The June 8 incident was followed by another two attacks on NATO supply convoy, one in Quetta, leaving one NATO oil tanker seriously damaged, and the other in Peshawar, in which three NATO oil tankers were burnt.