The appeal to the government of Indonesian President Susilo Bambang Yudhoyono from the Setara Institute for Democracy and Peace came as the country was hit by two instances of such violence in less than a week. The president has denounced these acts.
On Tuesday, three churches and a courthouse in the Central Java town of Temanggung were attacked by Muslim mobs irate over what they saw as a light sentence against a Christian accused of blaspheming Islam in books and articles he distributed in October of last year, The Jakarta Post reported.
Indonesia, the world's largest Muslim-majority nation, is a secular democracy.
In the other incident Sunday, members of the Ahmadiyah sect were attacked, resulting in the deaths of three people and injuries to several more. The Ahmadiyahs are not accepted as a part of Islam by mainstream Muslims.
In its appeal, Setara Chairman Hendardi said the state cannot remain silent in the face of religious intolerance and violence.
He blamed such incidents on the government's refusal to accept inputs from those who disagree with the hard-liners' defiance of the law. He said his institute recorded 75 cases of religious intolerance last year, the report said.
Separately, Antara said Archbishop Johannes Pujasumarta deplored the church attacks, saying, "I urge Catholics to remain smart and not to be emotional and take violent acts to respond to violence."
The national police reported they had arrested one suspect in the incident.
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