An explosion at a gas station in Russia’s southern region of Chechnya killed at least four people, officials said Saturday.

The explosion of a gas tank triggered a fire at the service station in the regional capital, Grozny, said Russia’s Emergencies Ministry, adding that two children were among the dead. The fire was extinguished.

Grozny is about 1,500 kilometers (930 miles) south of Moscow.

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Regional authorities said a criminal investigation was opened.

Last month an explosion at a gas station in the neighboring region of Dagestan killed at least 13 people and injured 23 others.