Another suicide bomber blew himself up at the Imam Khomeini mausoleum in Tehran on Wednesday, Iranian state television.
There are no immediate reports of causalities.
Al-Arabiya, Saudi-owned television news channel, reported that two of the mausoleum attackers were women. One of them blew herself up, while the other was detained.
Some details of the mausoleum attack emerged. Three of the attackers fired at people, another activated an explosive device, as a result of which, one person died and five others were injured.