Islamic State issued a video on Wednesday threatening new attacks in the Iranian capital Tehran and calling on young Iranians to rise up.
A man wearing a black ski mask and holding an AK-47, seated alongside two others, made the threat in a video bearing the Islamic State's Amaq news agency logo and showing footage of two attacks in Tehran in June claimed by the militant group.
"The same way we are cutting the necks of your dogs in Iraq and Syria we will cut your necks in the center of Tehran," the man said, speaking accented Farsi.
Islamic State, a Sunni Muslim group which has sought to establish a caliphate in parts of the Gulf but is now under pressure from national armies and international groups in Syria and Iraq, sees Iran, which is predominantly Shia, as one of its biggest enemies in the region.
The group killed at least 18 people in attacks on parliament in Tehran and the mausoleum of Ayatollah Khomeini on June 7.
Iran's Revolutionary Guards fired several missiles at Islamic State bases in Syria on June 18 in response to that attack. Iranian officials have also announced the arrests of dozens allegedly linked to the attacks.
Another portion of the video showed militants in black ski masks speaking out against Shias in Arabic and threatening attacks against them in Iraq.