Authorities in Shi’ite-ruled Iran say they have foiled several terrorist attacks planned across their country by sympathizers of Islamic State militants.

Ali Shamkhani, the head of Iran’s National Security Council, told the state-run ISNA news agency on June 20 that a group of IS sympathizers was arrested in Tehran on charges of plotting terrorist attacks across the country.

The IS militant group is led by radicalized Sunni Muslim extremists who consider Shi’a Islam to be heretical.

In March, U.S. Secretary of State John Kerry declared that violence initiated by IS militants against Shi’ite Muslims in Syria and Iraq amounted to genocide.

The U.S. House of Representatives in March also classified atrocities committed by IS against certain ethnic and religious minorities as genocide.

Based on reporting by AP, dpa, and ISNA