The gunman, released on bail on January 1, opened fire at two houses in the central city of Arak.
A murder suspect freed on bail killed six people including a policeman and three family members in a shooting rampage Wednesday in central Iran, media reported.
The 26-year-old entered two houses in Arak and shot eight people with a Kalashnikov, killing five of them instantly, ISNA news agency quoted the city's prosecutor as saying. The shooter is still on the run but his brother, who allegedly accompanied him in the rampage, has been arrested, the prosecutor said.
A sixth victim later died in hospital and another was in critical condition, he added.
The first house targeted was the home of a police officer who had arrested the man last year on charges of complicity in a murder.
The officer, his sister, mother and brother were all killed while another family member was hospitalised.
The suspect then went to the house of the victim who he and two others are accused of killing last year and shot dead his parents. Their son was also injured.
The gunman had been released on bail of two billion riyals ($50,000) on January 1. Gun violence is rare in the Islamic republic and offenders face severe punishment.