"We are trying to identify the person and find out his motivation," Mohsen Hamedani added.
The man was wielding a large knife, according to Tasnim news agency, and was wearing white shroud, symbolising his readiness to sacrifice his life.
The attacker was shot at leg when trying to pass the security gate of the presidential office in Pasteur Street in central Tehran. It is a high security area as other key government institutions are also located there.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)