COLOMBO - Sri Lanka on Wednesday blocked access to Facebook and suspended internet services in a troubled central district after police warned that rioters were using social media to spread anti-Muslim sentiment.

The government declared an island-wide state of emergency Tuesday and imposed curfews across Kandy after days of rioting claimed at least two lives and left Muslim homes and businesses in ruins.

Schools were shut across Kandy, a hill station popular with tourists, as rioters defied curfews and clashed with police who used teargas to disperse the mobs. A senior government source said Sri Lanka’s telecoms regulator had asked internet providers to block access to Facebook and other social media platforms to stop the unrest spreading.

“This is a temporary measure and we will have the restrictions removed soon,” a top official told AFP on condition of anonymity.

He said police had already identified anti-Muslim messages being shared on social networks, including a video posted by a hardline Buddhist monk urging violence against Muslims.

Authorities suspended internet access entirely to curfew-bound Kandy after discovering rioters were using online messaging services like WhatsApp to coordinate attacks on Muslim properties.

Sri Lankan telecoms providers said they would be blocking certain social networks following an order from the island’s regulator.

“Access to certain social media sites and messaging platforms will be restricted with immediate effect until further notice,” Sri Lanka’s largest mobile phone provider Dialog said in a statement.

The internet blackout in Kandy, 115 kilometres east of Colombo, has also affected media organisations to get pictures and video footage from the region. Censorship and media oppression was used widely by strongman president Mahinda Rajapakse, who for a decade in power ordered local internet providers to block anti-government sentiment online.

His successor President Maithripala Sirisena was elected in 2015 promising an end to draconian government restrictions, but some websites critical of the government remain blocked.

Meanwhile, mobs torched Muslim-owned businesses in Kandy on Wednesday as hundreds of police and troops struggled to restore order after days of rioting.

The soldiers poured into Kandy to reinforce police but arson attacks persisted even though the government has imposed a nationwide state of emergency and suspended the internet locally to quell attacks by mobs from the majority Sinhalese community.

An evening curfew was extended till Thursday evening in the troubled hill district popular with tourists, officials said.

Schools were shut across Kandy, a hill resort famed for its tea and Buddhist relics, as rioters defied curfews and clashed with police who used tear gas to disperse them.

Government spokesman Rajitha Senaratne vowed those responsible for the lawlessness would be punished. “This is organised violence,” Senaratne said in Colombo. “We have identified four individuals behind the riots and they will be arrested soon.”

He said police were also ordered to detain those accused of spreading messages fomenting hate against Muslims via social media.

At least three police officers were wounded overnight at Menikhinna, a suburb of Kandy which has been a focus of the new trouble, said police spokesman Ruwan Gunasekera.

Foreign governments issued travel warnings after Sri Lankan authorities granted sweeping powers to police and troops to arrest and detain suspects.

“The state of emergency may include curfews in specific locations,” the UK government said on its website. “You should exercise caution, avoid protests and rallies and comply with local security requirements.”

The US State Department said further violence was possible and advised visitors to monitor local media for updates. The United Nations condemned the violence and urged Colombo “to ensure that appropriate measures are swiftly taken to restore normalcy in affected areas”.

More than 150 homes, shops and vehicles belonging to Muslims were set ablaze by mobs of Sinhalese rioters Monday and Tuesday.

The violence began after a man from the mainly Buddhist Sinhalese majority died at the hands of a Muslim mob last week. The trouble escalated when a Muslim man was found dead in a burned building on Tuesday.

The Sinhalese are the majority ethnic group in Sri Lanka, making up 75 percent of its 21 million people. Muslims make up 10 percent.There was no immediate estimate of the damage from Wednesday’s arson attacks.