Indian police made fresh arrests in the case of the Hindu tailor’s execution in Rajasthan, a murder that sparked unrest between the Hindu majority and Muslim minority and resulted in a crackdown on demonstrations and online activity to prevent tensions from rising.

The murder of the tailor last week in his shop in Udaipur, a well-liked tourist destination filled with lakes and palace hotels, was planned, according to three top police officials who said this on Saturday. Two Muslim men based in the northwest state were detained for this.

“We have now arrested the two masterminds and previously we had arrested two men who committed the heinous crime,” said Prafulla Kumar, a senior police official based in Udaipur.

Kumar said internet services was being gradually restored and security forces continued to be on alert following the murder, carried out by two Muslim men now under arrest who filmed the act and posted it online.

The perpetrators said the act was in response to victim’s support for a politician’s derogatory remarks about the Prophet Mohammad. The victim, Kanhaiya Lal Teli, had allegedly put up a social media post supporting a former spokesperson for Prime Minister Narendra Modi’s party who made anti-Islam comments in May.

On Friday judges from the Supreme Court of India stated the ex-spokesperson, Nupur Sharma, must apologise to the whole nation after the remarks intensified religious fault lines in India, angered Islamic nations and triggered diplomatic strains.

In India, at least two demonstrators were killed in police fire during protests against Sharma’s comments.

In Afghanistan, the militant group Islamic State last month claimed an attack on a Sikh temple that killed at least two people and injured seven was in response to insults levelled at the Prophet Mohammad in India.

Police in New Delhi arrested journalist Mohammed Zubair, a vocal critic of the Modi government, who had helped draw attention to Sharma’s remarks through his fact-checking website Alt News and on social media.

The National Investigative Agency (NIA)- India’s top anti-terrorism agency – said they carrying out a probe in the Hindu tailor’s killing.

A senior NIA official in New Delhi said they were questioning Muslims linked with the four accused in Udaipur to identify whether they had links with militant networks.

Muslims living about 3 kilometres from the tailor’s shop where the victim was killed said they felt nervous and feared a social and economic boycott by powerful Hindus residing in Udaipur.

“I know what has been done is barbaric but the community should not be held responsible for the deed of two people,” said Mohammad Farukh, a medical representative living in a Muslim-dominated area of the city.

The All India Muslim Personal Law Board called the incident “highly condemnable”, adding that it was against both Indian law and Islamic strictures.