Sri Lankan authorities on Thursday lifted the curfew, which was imposed in the Western province after the eruption of violence in the capital here, even as President Gotabaya Rajapaksa, who has fled to the Maldives, was yet to submit his resignation letter.

Rajapaksa, the 73-year-old leader who had promised to resign on Wednesday, appointed Prime Minister Ranil Wickremesinghe as the acting President hours after he fled the country, escalating the political crisis and triggering a fresh wave of protests.

At least 84 people were hospitalised when protesters clashed with the security forces at the prime minister's office and at the main access junction to Parliament since mid-afternoon on Wednesday after Rajapaksa fled the country.

The police fired tear gas and water cannons at the mob who were trying to break barriers and enter the restricted zone.

The police spokesman Nihal Thalduwa said protesters had grabbed a T56 firearm and 60 bullets from a Sri Lanka Army soldier. A police complaint had been lodged, the police said.

Authorities had to impose a curfew in the Western province following the eruption of violence.

Wednesday's protests were more directed at Wickremesinghe. Calls for his resignation intensified after he was appointed the acting president.

Political party leaders are asking him to step down so that Speaker Mahinda Yapa Abeywardena can take control as acting president.

Wickremesinghe in a statement asked the Speaker to find a suitable nominee to become the prime minister in an all-party interim government.

However, the protesters have demanded that the interim government must only consist of politicians acceptable to them.

Meanwhile, President Rajapaksa failed to send in his resignation on Wednesday as pledged earlier.

He was likely to send his resignation letter only after reaching his final destination on Wednesday evening, Sri Lanka's The Morning news portal reported.

The media here cited sources in the Maldives as saying that Rajapaksa had failed to board the Singapore-bound flight from Male due to security concerns on Wednesday night.

Rajapaksa reportedly had raised security concerns about taking a civilian flight and was urging the Maldives authorities for a private jet to land in Singapore.

Meanwhile, the protesters continued to occupy the key administrative buildings they had seized since Saturday. There is an endless stream of sight-seers at the buildings. Videos show the properties have suffered serious damages since they were occupied.

The protesters stressed that they would only hand over the properties to authorities after an interim government would be in place.

The influential Buddhist clergy chiefs in a statement called for an end to violence. They said the country's security was in grave danger and Parliament must be summoned immediately to work out a political solution.

Rajapaksa, who enjoys immunity from prosecution while he is president, fled the country before resigning to avoid the possibility of arrest by the new government.

On Saturday after thousands of protesters stormed his official residence, blaming him for the unprecedented economic crisis that has brought the country to its knees, Rajapaksa announced that he will step down on Wednesday.

Rajapaksa's escape to the Maldives was negotiated by the Maldivian Majlis (Parliament) Speaker and former president Mohamed Nasheed, sources in the Maldives capital Male said.

Sri Lanka, a country of 22 million people, is under the grip of an unprecedented economic turmoil, the worst in seven decades, leaving millions struggling to buy food, medicine, fuel and other essentials.

Last week, Prime Minister Wickremesinghe said Sri Lanka is now a bankrupt country.