TEHRAN, Young Journalists Club (YJC) - The attack targeted a police van, media said.
Media sources say it is a suicide attack.
Al-Sharq ul-Ausat announced that Daesh (ISIS) claimed the responsibilty of the suicide attack.
Polls have opened as hundreds of thousands of troops are deployed to secure an election, which is said to be the most consequential one that would lead to a rare democratic transition of power in the country's 71-year history.
Voting began across 85,000 booths at 8 a.m. local time and will close at 6 p.m. on Wednesday.
The final outcome is expected to be announced within 24 hours after the polling, but preliminary results will be out late at night.