Rafiq Sherzai, spokesman for the Herat Regional Hospital, said on Tuesday that 18 people were also wounded in the blast late Monday.
He says the blast happened inside the compound of a gas supply company adjacent to a camp for internally displaced people. The explosion was so powerful that the burning truck was flung into the camp, he says.
Of the 11 dead, 10 were children, he says. Four of the wounded were sent to Iran for treatment with burns to more than 90 percent of their body, Sherzai says.
Gas explosions are not uncommon in Afghanistan, where bottled gas is used for household cooking nationwide.
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