Jakarta - Pressure mounted Tuesday for the Indonesian government to outlaw the Muslim hardline group Islamic Defenders Front (FPI) following a violent attack over the weekend by followers against interfaith supporters.

In east Java provinces, hundreds of Nahdlatul Ulama supporters - Indonesia's largest Islamic organization - rallied demanding that the government disband the FPI. In a similar protest Monday in Jogjakarta, central Java, one person was injured during a scuffle with supporters of the hardliner group.

Indonesian police have identified five FPI activists as suspects in Sunday's attacks on participants in a religious tolerance rally in the capital, leaving nearly 30 people injured.

They were rallying against a possible government ban on the minority Ahmadiyah sect, deemed deviant by religious authorities in the country.

The violent attack triggered condemnation from community and religious leaders, including NU and the country's second largest Islamic organization Muhammadiyah, calling for the perpetrators to "be prosecuted."

In response, FPI leaders on Monday night threatened to wage war on the Ahmadiyah sect unless President Susilo Bambang Yudhoyono bans it within three days.

Habib Rizieq, chairman of FPI, claimed that his supporters attacked Sunday's gathering, billed as the National Alliance for the Freedom of Faith and Religion, because it supported the "deviant" Ahmadiyah minority sect.

Rizieq, who was for seven month in 2004 for inciting vandalism on entertainment spots in the capital Jakarta, vowed that his supporters would fight "until our last drop of blood" to resist attempts to arrest them.

Ahmadiyah has been a target of attacks since a government commission recommended in April that the minority sect be outlawed.

The Indonesian Ulema Council, the country's highest authority on Islam, has declared the Ahmadiyah sect "heretical" for believing its founder, Mirza Ghulam Ahmad, who died in 1908 in India, is the last prophet, not Mohammed, who mainstream Muslims worldwide believe was God's final messenger.

However, human rights activists and civil liberties groups, argue that followers of Ahmadiyah are protected under Indonesia's constitution, which guarantees the right to religious freedom.

Indonesia is home to the world's most populous Islamic nation with nearly 88 per cent of its 225 million people being Muslims. The country has a long history of religious tolerance. (dpa)