Unidentified assailants on Friday blew up a Nato oil tanker near the western by-pass in Quetta, a private television channel reported. The Afghanistan-bound oil tanker that started travelling from Karachi had reached Quettas Akhtarabad area early on Friday, police said. The driver pulled up the tanker at a petrol pump and after a while the tanker exploded, with the oil spilling out. Police arrested two suspects who were attempting to flee from the scene and started an investigation.