The crisis turned volatile earlier this week after pro-government supporters began attacking a camp of peaceful demonstrators who had been protesting against the government and the devastating economic crisis that has engulfed the island of 22 million people.
As footage emerged on Wednesday of armoured military vehicles in Colombo and military checkpoints being set up across the country , fears grew that the path was being laid for a military takeover.
A nationwide curfew has done nothing to stop protesters gathering to demand the resignation of the president, Gotabaya Rajapaksa, who stands accused of economic mismanagement and corruption that has left it in its worst financial crisis since independence.
Security officials confirmed they had been ordered to use "live ammunition" on those found to be involved in violence or vandalism, alleging that outbreaks of violence were a "coordinated" campaign.
Eight people have been killed and more than 200 injured in the violence that has ensued across the country since Monday's attacks by pro-government supporters. Mahinda Rajapaksa, the brother of the president, who resigned as prime minister on Monday following mounting public pressure, had to be evacuated at dawn on Tuesday from his official residence in Colombo after protesters tried to storm the building. He is currently sheltering at a naval base in the north-eastern city of Trincomalee.
More than 100 buildings were set alight, including the homes of 41 pro-Rajapaksa politicians and a luxury hotel said to be owned by the Rajapaksas, as well as several buses that had been rumoured to be used as transport for pro-Rajapaksa supporters.
Forming an interim government is a matter of urgency for Sri Lanka, both to ensure the country's economic situation does not worsen further and to continue vital negotiations with the International Monetary Fund, which the country is relying on for financial support and billions in emergency loans.
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The central bank chief warned on Wednesday that Sri Lanka's economy will "collapse" unless a new government is urgently appointed and said he would resign if an interim prime minister wasn't appointed within days.
In an address to the nation on Wednesday night, Gotabaya Rajapaksa said he would appoint a new prime minister and cabinet within the week and promised to take steps towards abolishing the executive presidency, as was demanded by the opposition. However, he stopped short of resigning.
"After the country is stable under the new Government, I will speak to everyone and create an environment for the abolishment of the executive presidency," said Rajapaksa.
Many expressed concern that the military might try to step into the power vacuum left by the dissolved parliament. But speaking at a news conference, the defence ministry's top official, Kamal Gunaratne, denied allegations of a military takeover. "None of our officers have a desire to take over the government. It has never happened in our country and it is not easy to do it here," said Gunaratne.
Sajith Premadasa, the leader of the main opposition SJP party who has refused to participate in a government under the Rajapaksas, accused the government of orchestrating mob violence in order to bring in martial law.
"In the guise of angry mobs, violence is being incited so military rule can be established," he said. "Rule of law should be maintained through the constitution, not with guns. It is time to empower citizens, not disempower them."
The US state department expressed concern over the military deployment in Sri Lanka. "We stress that peaceful protesters should never be subjected to violence or intimidation, whether that's on the part of the military force or civilian units," said a spokesperson, Ned Price.
On Wednesday, Pope Francis appealed for calm in Sri Lanka and for authorities to "listen to the aspirations of the people".
"I offer a special thought to the people of Sri Lanka, in particular to the young, who in recent times have made their cry heard in the face of the country's social and economic challenges and problems," he said at the end of his weekly audience.