Comments come over planned protests by conservative Muslims over blasphemy claims after demonstration drew 100,000.

Indonesian President Joko Widodo says he’s determined to “prevent the growth of radicalism” after reports that Muslim conservatives are planning protests to destabilise his government.

Officials say there has been mounting alarm in the government since more than 100,000 people – led by a group called the Islamic Defenders Front – took to the streets of Jakarta on November 4 to demand the removal of the capital’s governor – a Christian – for alleged blasphemy.

Widodo blamed “political actors” for fanning violence during the massive protest, without naming anyone.

The president 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 emphasise the spirit of pluralism,” Widodo told reporters after the meeting at the presidential palace. “The government is determined to prevent the growth of radicalism in this country.”

National Police Chief Tito Karnavian warned on Monday of a threat to parliament during rallies expected this Friday and on December 2.

“There are hidden methods by certain groups to enter and occupy parliament,” Indonesian media quoted Karnavian as saying.

“If [these actions] are intended to overthrow the government, that’s a violation of the law.”

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Widodo and the leader of his party, Megawati Sukarnoputri, along with opposition leader Prabowo Subianto have all called for calm.

On Tuesday, the president tried to assuage concerns among investors in Southeast Asia’s largest economy.

“The political situation has been a little heated recently, but this is very normal around elections,” he later said in a speech, referring to upcoming local elections in Jakarta.

“There is no reason to be pessimistic,” Widodo told the event attended by bankers, investors, and top company executives, adding inflation and growth were both in line with government targets.

‘A little heated’

The trigger for the tensions 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 Quran in political campaigning.

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.

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Purnama apologised for the remarks, but his opponents have built a groundswell of support calling for his arrest and incarceration under Indonesia’s tough blasphemy laws.

Police have opened an investigation into the allegations that Purnama insulted the Quran 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 of blasphemy.

Police said they were investigating a social media campaign calling for a run on banks on Friday in protest over the government’s handling of the complaint against Purnama. Government officials have urged the public not to participate and played down the potential impact of any such campaign.

Indonesia – a country of 250 million people – has the world’s largest Muslim population and is also home to Christian and Hindu communities.