A suicide car bomber on December 6 attacked a police headquarters in the Iranian port city of Chabahar, killing at least two people and wounding up to two dozen others, according to state TV.

The TV station broke into its regular broadcast to report what is a rare type of attack in the Islamic Republic. However, with largely Shiite Muslim Iran having fought bitter battles against Islamic State in Syria and engaged in fending off an economic attack from the US—Iranian security officials claim Tehran’s regional enemies are taking this as an opportunity to step up their backing for terrorists in Iran while it feels the economic and social strain—Sunni Islamist militant and terrorist groups have mounted other notable attacks in the country in the past two years.

In September, gunmen disguised as soldiers opened fire on a military parade in Ahvaz, killing and wounding dozens. Arab separatists and Islamic State both claimed responsibility. In June 2017, a twin Islamic State assault on the parliament and the shrine of Ayatollah Ruhollah Khomeini in Tehran killed at least 18 people and wounded more than 50.

Rahmdel Bameri, Chabahar’s acting governor, said a suicide attacker driving a vehicle loaded with explosives drove up to the police headquarters, reported The Associated Press. Officers blocked the vehicle and started firing at the driver, who then detonated his explosives. Footage showed smoke rising over the city.

Iranian media have initially pinned the attack on Ansar al-Furqan, a Sunni jihadi group.

Ansar al-Furqan is known to operate in Iran’s southeastern Sistan and Baluchistan province, which sees periodic attacks by Baluch separatists and drug traffickers. A year ago the group claimed to have blown up an oil pipeline in Iran’s southern Khuzestan province.

Chabahar is on Iran’s southeastern coast near the border with Pakistan. It is the location of the country’s only oceanic port. The port complex is being jointly developed by India. As it cannot export to Afghanistan and Central Asia via its arch-rival Pakistan, India wants to send cargoes via the Indian Ocean and Chabahar. The US has granted a special waiver to India allowing it to work with the Iranians to develop the port facilities without fear of getting hit by the heavy sanctions Washington has reimposed on Tehran. The Trump administration is attempting to throttle Iran’s economy to force the Iranian government to renegotiate the Islamic Republic’s policies and activities in the Middle East, including its support for militants in Syria, Iraq, Yemen and Lebanon.