At least 11 people were killed and 59 wounded Tuesday when a gas cylinder exploded and started a fire inside an oil tanker being broken up for scrap in southern Pakistan, officials said. The accident happened at the Gadani shipbreaking yard in the southwestern province of Balochistan, some 50 kilometres (30 miles) west of Karachi. "A gas cylinder explosion caused a huge fire in the ship which was being dismantled," Balochistan home secretary Akbar Harifal told AFP, ruling out a deliberate attack. "We have recovered at least 11 bodies so far and shifted 59 injured to Karachi," Zulfiqar Ali Shah, the deputy commissioner of the area, told AFP. "All the injured had severe burns," he added. Local government official Zulfiqar Hashmi told AFP the ship was still ablaze and there was not enough equipment to extinguish it. Both he and Shah said Pakistan Navy firefighters had been called in to help. TV footage showed a thick plume of black smoke rising from the ship as local rescue workers rushed to the scene. Prime Minister Nawaz Sharif expressed his "deep grief and sorrow" over the incident, according to a statement by his office. Industrial accidents are common in Pakistan, with workplaces often forgoing basic safety measures and equipment in the absence of legislation to protect labourers.