Dozens of Indonesian mosques are preaching extremism, including violence against non-Muslims, to government workers, the country’s intelligence agency has warned.

The alarming findings of the Indonesian State Intelligence Agency follow Indonesia’s worst terrorist attack in a decade when three churches and a police station were bombed in the city of Surabaya in May, killing 28 people. Islamic State of Iraq and the Levant (Isil) claimed responsibility for the bombings.

In a chilling development, child suicide bombers were among the attackers in the deadly assault, once again raising fears about the growing influence of hardline Islamism and the decline of religious tolerance in the world’s most populous Muslim nation.

According to AFP, the intelligence agency revealed it had probed about 1,000 mosques across the Southeast Asian country since July, and discovered that imams at some 41 places of worship in one neighbourhood in the capital, Jakarta, were preaching extremism to worshippers.