TEHRAN, Iran — A gunman opened fire Sunday night at a prominent shrine in southern Iran, killing one person and wounding eight others in an attack that followed another assault there months earlier, authorities said.

Officials offered no immediate motive for the attack in the city of Shiraz at Shah Cheragh, which draws Shiite pilgrims to its domed mosque and the tomb of a prominent member of the faith from its earliest days.

However, Iran has faced attacks in the past from the Sunni extremists of the Islamic State group, who view Shiites as heretics. Iran also faces lingering unrest and economic turmoil amid tensions with the West.

Iran’s state-run IRNA news agency quoted Ismail Qezelsofla, a deputy governor for security in the country’s Fars province, as offering the casualty toll.

Fars province Gov. Mohammad Hadi Imanieh told Iranian state television that a single gunman carried out the attack and later was detained by security forces. He did not offer any motive for the attack in his brief comments.

Footage after the attack showed security forces surround one entrance to the then-deserted courtyard of Shah Cheragh at sunset. Ambulances later took away the wounded as security forces and government officials reached the shrine.

Shah Cheragh is one of Iran’s top five Shiite shrines. It draws pilgrims to Shiraz, which is some 675 kilometers (420 miles) south of Iran’s capital, Tehran.

No group immediately claimed responsibility for the attack.

The attack Sunday night comes after an October 2022 attack on the same shrine killed 13 people and wounded dozens of others. The Islamic State group claimed the assault, which Iran said had been carried out by a man from Tajikistan, who later died in a hospital after succumbing to injuries he suffered while being detained by security forces.

Iran has backed Syria’s embattled Bashar Assad during his country’s civil war. It also fought Islamic State fighters both there and in Iraq.

The worst assault from Islamic State militants in Iran came in a June 2017 attack that killed at least 18 people and wounded more than 50 in Tehran as its gunmen stormed parliament and Ayatollah Ruhollah Khomeini’s mausoleum. Khomeini led the 1979 Islamic Revolution that toppled the Western-backed shah to become Iran’s first supreme leader until his death in 1989.