Iran’s army says four of its servicemen were killed and eight others wounded when a soldier opened fire on his colleagues at a military base.
A statement said the incident took place on August 6 at a shooting range in the town of Kahrizak, about 10 kilometers south of Tehran.
It said the shooting was "probably related to psychological problems of the soldier who suddenly started firing at his comrades."
It could also have been the result of "the sudden and accidental swiveling of a weapon," the statement also said.
But the head of the Kahrizak city council, Mohammad Hashemi is quoted by Mehr news agency as saying that, "A serviceman from Sistan-Baluchestan province opened fire at his comrades" and other soldiers returned fire at the assailant who died from his gunshot wounds.
He put the number of the injured at 12.
Last month, state media reported a similar incident when a serviceman opened fire at a barracks in the town of Abyek, northwest of Tehran, killing three and injuring six.
The gunman, who shot himself but survived his injuries, had suffered from "temporary psychosis," according to the ISNA news agency.
Military service of up to 24 months is mandatory in Iran for men aged 19 and above.