Two people were killed and seven others injured late Sunday when two gunmen opened fire at a shrine in southern Iran's Shiraz.
The armed assailants opened indiscriminate fire at the entrance of the Shah Cheragh shrine resulting in the death of a guard, the governor's office and shrine officials told state-run IRIB news.
Fars province chief justice Kazem Mousavi told the judiciary's Mizan Online news website that "eight people suspected of links with the terrorist attack... have been arrested."
"All the people arrested are foreigners," he said without elaborating.
The main suspect was arrested on Sunday night shortly after the attack, and Mizan identified him as Rahmatollah Nowruzof from Tajikistan.
Iran's state TV cited BBC as saying that Daesh claimed responsibility for the attack.
Gen. Bo Ali, the Revolutionary Guard commander in Fars province, of which Shiraz is the capital, told state TV that the assailant who was taken into custody was carrying a rifle and eight magazines, adding that the situation was currently under control.
President Ebrahim Raisi has asked the Interior Ministry and the provincial governor's office to "quickly identify all the perpetrators" of the attack, according to state media.
Interior Minister Ahmad Vahidi instructed the provincial governor of Fars to investigate "the terrorist incident."
The national security commission of the Iranian parliament will also be investigating the attack Monday, the commission spokesman was quoted as saying, adding that the report will be made public soon.
The European Union and several countries including Iraq, Russia and France have condemned Sunday's shooting and expressed their condolences.
Baghdad rejects "terrorism in all its forms" and stands "with the international community in confronting terrorism", said foreign ministry spokesman Ahmed al-Sahhaf.
Second attack on shrine
The 12th-century shrine, which houses the grave of a revered Shia scholar, is a popular destination for local and foreign tourists.
Last October, at least 13 people were killed and 40 others injured after an armed man opened an indiscriminate fire inside the shrine.
It was the first major attack in Iran claimed by Daesh since 2017, when five armed men attacked the Iranian parliament and the mausoleum of the country’s founder, Ayatollah Khomeini, in Tehran.
In July, Iranian judicial authorities publicly executed two men over involvement in the attack.