Indonesian President Joko Widodo said on Tuesday he was determined to “prevent the growth of radicalism”, apparently responding to rumors that Islamist extremists were planning protests to destabilize his government.

Officials say there has been mounting alarm within the government since more than 100,000 Muslims, led by hardliners, took to the streets of Jakarta on Nov. 4 to demand the ouster of the capital’s governor, a Christian, over alleged blasphemy.

National Police Chief Tito Karnavian warned on Monday that certain groups may try to storm parliament during rallies that are expected this Friday and on Dec. 2.

“There are hidden methods by certain groups to enter and occupy parliament… If (these actions) are intended to overthrow the government, that’s a violation of the law,” Karnavian said, according to media.

Widodo has blamed “political actors” for fanning violence that erupted during the Nov. 4 protest, though he has not named anyone.

Analysts have said opponents of Widodo, the first Indonesian president to have come from outside the political elite or military, are using the Islamic furor over the Jakarta governor to undermine him.

Widodo held talks with a senior coalition partner on Tuesday, the latest in a series of meetings with top political, religious and military officials to signal the unity of his government and support from the security establishment.

“I want to emphasize the spirit of pluralism … and the government is determined to prevent the growth of radicalism in this country,” he told reporters after the meeting at the presidential palace.

Widodo has met repeatedly with the military and called for security forces to be on alert against further unrest.

He has also met with top politicians, including the leader of his backing party, Megawati Sukarnoputri, and opposition leader Prabowo Subianto. The three have jointly called for calm.

The trigger for the tension was a comment that Jakarta governor Basuki Tjahaja Purnama, the first Christian and ethnic Chinese in the job, made about his opponents’ use of the Koran in political campaigning.

Indonesia has the world’s largest Muslim population and is also home to sizeable Christian and Hindu populations.

Purnama, popularly known as Ahok, is running for re-election in February against two Muslim candidates, including the son of former President Susilo Bambang Yudhoyono. Widodo has been seen as one of the governor’s main supporters.

Police have opened a probe into allegations Purnama insulted the Koran and questioned him on Tuesday. Prosecutors are expected to bring a case to court in the coming weeks. He could face up to five years in prison if found guilty.

Officials are also investigating a social media campaign calling for a run on banks on Nov. 25 in protest over the government’s handling of the complaint against Purnama, the police press relations department said on Twitter.

“It is our shared responsibility not to follow suggestions that are intended to inflict damage,” Finance Minister Sri Mulyani Indrawati told reporters on Monday, in response to a question about a possible run on banks. “…Economic recovery and stability are very important for the public.”

(Additional reporting by Cindy Silviana, Fransiska Nangoy and Jakarta bureau; Editing by John Chalmers and Nick Macfie)