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.
The semiofficial Mehr news agency reported that the dead included a commander and three soldiers, including the assailant who was killed in a shoot-out with other servicemen.
The military 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.
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 injured soldiers were transported to a medical center and an investigation has been opened, the statement added.
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.