"An explosion went off on a gas pipeline near a checkpoint guarded by federal troops at 6:40 Moscow time (3:40 GMT)," said Timur Taisumov, spokesman for the Chechen Republic's emergencies department. "A mine is believed to have been activated at the scene."
He said the gas supply was cut off and the blaze promptly extinguished. Some 3,000 people in the nearby Kirov town were left without gas.
Investigation into the blast has been launched and repairs are under way on the pipeline.
Chechnya, the scene of two bloody military campaigns in the late 1990s-early 2000s, is still plagued by sporadic fighting and terrorist attacks despite a widely publicized amnesty for separatists announced by authorities. Violence has spilled over to other neighboring North Caucasus republics.
