Iran says it has killed the alleged "mastermind" of the terrorist attacks in Tehran last week claimed by the Islamic State.

Iran's intelligence minister, Mahmoud Alavi, declared on state televsion late Saturday night Iranian intelligence operatives killed the "commander of the team" that carried out the strikes, the Washington Post reported.

The suspect, whose name was not revealed, was "sent to hell" Alavi said.

The suspect fled the country after the attacks last week at Iran's Parliament building and the mausoleum of Ayatollah Ruhollah Khomeini, the founder of the Islamic republic, which killed 17 people.

It was the first successful terrorist attack in Iran, which is predominantly Shiite Muslim, by the Islamic State, a Sunni terrorist group.

Iranian investigators are focusing on Iranian Kurds affiliated with ISIS as the perpetrators of the attacks.