Cause of the blast, while still unconfirmed, is said to be due to careless welding work being undertaken near the tanker, which is believed to have been carrying 18,000 litres of petrol.

Speaking before the latest casualty figures were released, provincial police chief Zia-Ulldin Mahmodi said, “The truck explodes and the result is 31 people killed, 35 injured. Probably half of the injured people will also die as their injuries are very bad; they have 100% burns.”

According to a spokeswoman for French non-governmental organisation Medecins du Monde France, Valerie Gentner, “About 31 people had died at the scene while another three had succumbed to their injuries after arriving at Herat hospital. Twenty-six people [are] being treated for burns while other casualties [are] being dealt with at a clinic in Shindand.”

“[My organisation] had brought some medicine to the hospital but, like most of Afghanistan's medical facilities, it was not equipped to deal with the emergency,” added Gentner.

Afghan president, Hamid Karzai, is said to be “deeply saddened by the news of the terrible accident”.