The government is considering suspending the Islam Defenders Front (FPI) for its attack on activists Sunday at the National Monument (Monas).
Coordinating Minister for Politics, Law and Security Widodo Adi Sucipto said Monday the government was looking at a 1985 law that allows for the suspension of a mass organization.
The decision was made in a meeting led by President Susilo Bambang Yudhoyono on Monday evening to discuss proper measures against the hard-liners following the attack.
"We should not only see this problem as a violent action, but as something that may tarnish our country's civilization," Widodo told a news conference after the meeting at his office in Central Jakarta.
"We are now conducting strict legal processes in this case," he added.
Widodo said the President had ordered an investigation of the organization that ambushed activists from the National Alliance for the Freedom of Faith and Religion (AKKBB) at Monas, who were rallying to commemorate the 63rd year of Pancasila state ideology and also to support members of the Jamaah Ahmadiyah Islamic sect.
"I think the Home Ministry will study it further," he said when asked about the possibility of the government disbanding the FPI.
"We should put this problem within the context that every mass organization must be in line with the 1985 law."
Under the 1985 law, the government can freeze the central board of a mass organization if it commits an act harmful to order and security, receives foreign assistance without government consent or support foreign parties that could act counter to national interests.
Should an organization continue conducting unlawful activities, the law further gives the government power to disband it.
However, Attorney General Hendarman Supandji said there should be several steps taken by the government before suspending an organization.
"First, we issue them reprimands, then we go to the Supreme Court," he said.
Earlier Monday at the presidential office, Yudhoyono condemned the attack and ordered actions to be taken against the perpetrators.
"I am deeply concerned with what happened yesterday afternoon. I strongly condemn the attackers that caused injuries to our people," he said.
"Our nation is bound by the law and Constitution and is not a country that supports violent acts. In regard to this incident, the law must be upheld.
"Indonesia is a lawful state, not an anarchic state. We should not be defeated by violent actions."
The President also called on people to maintain order when staging demonstrations and ordered the police to be tough in the face of violence.
"The police should continue implementing preventive measures to avoid similar incidents. Be strict, but do not carry out excessive actions that may instigate new problems," he said.
Vice President Jusuf Kalla and House of Representatives Speaker Agung Laksono also denounced the attack and asked the authorities to arrest all those behind it.
"The incident has led our nation to sink deeper amid many economic problems including the fuel prices increases," Agung said.
At a press conference Monday, FPI leader Habib Rizieq Shihab declared war on members and supporters of Ahmadiyah.
"We will never allow for the arrest of a single member of our force before the government dissolves Ahmadiyah. We will fight to our last drop of blood," he said.
The government remained undecided on when it would issue a decree on Ahmadiyah.
"The joint ministerial decree is still being processed by the Religious Affairs Ministry, the Attorney General's Office and the Home Ministry, and we will announce it later," Widodo said. "In time, the government will issue its decision on this matter."