Syria's Intelligence Directorate foiled an attack by the IS group on the Sayeda Zeinab shrine in a Damascus suburb, state news agency Sana reported on Saturday.
It said members of the cell were arrested before they could detonate an explosion inside the shrine, which is a site of mass pilgrimage for Shi'ites.
The foiled attack will stoke fears that IS is hoping to stage a comeback in Syria following the fall last month of President Bashar al-Assad.
Some Syrians and foreign powers have worried that the country's new leaders, who are from the Hayat Tahrir al-Sham (HTS) group that forced Assad out on December 8, may impose strict Islamic governance on a country with numerous minority groups such as Druze, Kurds, Christians and Shi'ites.
But the announcement by Syria's de facto government that it thwarted an attack targeting Shi'ite Muslims comes amid reassurances it will protect religious minorities.
"The General Intelligence Directorate is utilizing all its resources to confront all attempts to target the Syrian people in all their diversity," an intelligence official told Sana.
The IS militant group has claimed previous attacks in and around the shrine, including last year and a bombing in 2017 that killed at least 40 people.
The granddaughter of the Prophet Mohammad, Sayeda Zeinab is venerated by Shi'ite Muslims and the mosque and shrine 10 km south of Damascus attracts pilgrims from around the region.
Defence of the shrine had been a rallying call during Syria's 13-year civil war that drew Shi'ite militiamen from around the region to back former Syrian president Bashar al-Assad.
But Assad's ouster last month significantly diminished the position of Shi'ite forces in Syria.

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