A senior Iranian commander vowed revenge on the Islamic State (IS) militants over decapitating an Iranian serviceman in Syria, Tasnim news agency reported on Friday.

Major General Qasem Soleimani, the commander of the Quds Force of Iran's Islamic Revolution Guards Corps (IRGC), pointed to the recent killing of Mohsen Hojaji and said that "the IS terrorist group committed a heinous and inhumane crime that is contrary to any Islamic or even humanitarian law."

Soleimani said that his forces will take retaliation for this "savage act" by eradicating terrorism from the Islamic world.

"These crimes committed (by terrorists) made us more resolved and determined to clean every place of the Islamic lands from their evil existence," Soleimani was quoted as saying.

Hojaji, a member of the Iranian advisory support team in Syria, had been taken hostage by the IS militants near the Iraqi border in Syria. On Aug. 9, it was announced that he was beheaded by the IS.

IS also issued a video threatening new attacks in the Iranian capital Tehran.

On June 7, the IS militants carried out twin operations in the capital Tehran on Iran's Parliament and the Mausoleum of Ayatollah Rouhollah Khomeini, leaving 17 killed and dozens injured.

Following the IS operation in Tehran, the IRGC fired six mid-range ballistic missiles, within a range of 650 to 700 km, at IS bases in Syria's eastern region of Deir ez-Zor in June 18.