Iranian police on Saturday announced the arrest of a senior operative of Islamic State with two other members of the group accused of planning a suicide attack during next week’s celebrations marking the end of the Muslim holy month of Ramadan.

The police said Mohammad Zaker, known as “Ramesh”, and the other two were arrested in Karaj, west of the capital Tehran, following clashes, according to Iranian media. Eight others accompanying the men were also detained, they said.

Islamic State, which harbours a virulent hatred for Iran’s dominant Shi’ite sect, claimed responsibility for two explosions in Iran in January that killed nearly 100 people and wounded scores at a memorial marking the fourth anniversary of the assassination of top commander Qassem Soleimani in Iraq in 2020 by a U.S. drone.

Iran arrested 35 people in January, including a commander of Islamic State’s Afghanistan-based branch ISIS-Khorasan (ISIS-K), who it said were linked to the twin bombings on Jan. 3 in the southeastern city of Kerman.

On March 22, in the deadliest attack inside Russia in 20 years, gunmen opened fire with automatic weapons at a concert hall near Moscow, killing at least 144 people in a rampage claimed by Islamic State.

U.S. intelligence sources said ISIS-K had carried out both the Jan. 3 attacks in Iran and the March 22 shootings in Moscow.

Sources familiar with the matter told Reuters that Iran had tipped off Russia of the possibility of a major attack on its soil

In 2022 Islamic State took responsibility for an attack on a Shi’ite shrine in Iran that killed 15 people. Earlier attacks claimed by Islamic State include twin bombings in 2017 that targeted Iran’s parliament and the tomb of the Islamic Republic’s founder, Ayatollah Ruhollah Khomeini.

Islamic State once occupied large swathes of Iraq and Syria, imposing a reign of terror and inspiring lone wolf attacks in Western countries.