Unidentified gunmen killed a senior member of Iran's prominent Revolutionary Guard outside his home in Tehran on Sunday.

The two assailants shot Col. Hassan Sayad Khodayari five times in his car in the heart of the capital, state media said.

Reports identified Khodayari only as a "defender of the shrine," a reference to Iranians who fight against the Daesh terrorist group in Syria and Iraq within the Guard’s elite Quds force that oversees operations abroad.

There was no immediate claim of responsibility for the attack.

Security forces were pursuing the suspected assailants, state TV reported, without offering further details or giving a motive for the killing.

The Islamic Revolutionary Guards Corps, the ideological arm of Iran's military, identified Khodai as a colonel.

In a statement posted on their website, the Guards also denounced a "terrorist act" they claimed was carried out by "elements linked to global arrogance" – a reference to the United States and its allies.