Tehran: Four Iranian soldiers were killed and eight others wounded by gunfire from one of their comrades on Sunday at a military base in Tehran.

The Iranian army said in a statement that the incident took place on the firing range of the Kahrizak base in the Iranian capital, Xinhau reported.

The note said that an investigation was ongoing to find out whether the shooting was an accident or an attack and suggested that the shooter might have suffered from psychological problems.

Iran has compulsory military service and both the shooter and the majority of the victims were conscripts.

The wounded soldiers were taken to a hospital.

Such incidents are not common in Iran, although a young conscript suffering from psychosis killed three comrades and wounded six others in a similar incident