According to Fars agency, one of the shooters attempted to escape the building but was captured while another blew himself up. 
Iran's IRIB news agency quoted an MP as saying there were a number of attackers at the parliament building, armed with AK-47 rifles.
"There were three attackers armed with two Kalashnikov rifles and one colt pistol," MP Elyas Hazrati was quoted as saying.
An injured victim sits on the street after a shooting incident in Iran 
A map shows the locations of the attacks, including the unconfirmed report of an attack at a metro station 
A journalist at the scene said: "I was inside the parliament when shooting happened. Everyone was shocked and scared. I saw two men shooting randomly."
The semi-official Tasnim news agency reported that two members of the public were also caught up in the shooting.
Unconfirmed reports also say eight people have been injured inside Ayatollah Khomeini's mausoleum.
Gunmen are also believed to have targeted the Holy Shrine mausoleum of Ayatollah Khomeini 
The Imam Khomeini Metro Station was said to have been targeted, but these reports have not been confirmed 
There are reports of one dead 
It is believed an explosive vest was also found in the holy mausoleum, but has now been neautralised.
The mausoleum is located several kilometres to the south of parliament, but happened at the same time and is believed to have been co-ordinated.
The identity and the motivation of all assailants is still unclear.
A witness told Reuters that security forces had massed inside and outside parliament.