"Based on primary reports, 1 killed, 5 injured in shooting spree at Imam Khomeini shrine," the Mehr news service posted on its Twitter account.
Three of the assailants shot tens of rounds at the people visiting the shrine, while the fourth one detonated himself in a suicide attack in front of a police station opposite the shrine, FarsNews reports.
Multiple Iranian outlets including Mehr reported earlier that a third assailant had reportedly detonated his suicide vest. The latter cited reports of two assailants being arrested at the site.
One of attackers arrested at mausoleum of Imam Khomeini, according to the statement of Tasnim News Agency Twitter.
The law enforcement and guards at the shrine said they have also defused another suicide vest at the scene, according to the FarsNews.
According to the latest reports, one of the assailants was killed in the clashes, a second one has committed suicide after swallowing a cyanide capsule, and the third one was a female and captured after clashes with the law enforcement troops.