A man plays a piano inside the Sri Lanka's Presidential Palace in Colombo. AFP

Sri Lanka's colonial-era presidential palace has embodied state authority for more than 200 years, but on Sunday it was the island's new symbol of "people power" after its occupant fled.

Thousands of men, women and children were pouring into the imposing state mansion queuing to sit on President Gotabaya Rajapaksa's chair on the upper floor while children and parents banged on a grand piano downstairs.

A twitter user wrote, “After storming President Gotabaya's house, protestors played song used by him during his election campaign on a piano. The song is,"Hero who will work for us, who will eternally love this mother land..."

In the imposing "Gordon Garden" park of the palace, chuckling families enjoyed a picnic lunch as shaven-headed Buddhist monks in saffron robes marvelled at the marble floors and central air conditioning.

"When leaders live in such luxury, they have no idea how the commoners manage," monk Sri Sumeda told reporters after travelling 50 kilometres (30 miles) to visit the palace for the first time.

Cash Returned

Millions of rupees in cash left behind by Sri Lanka's President Gotabaya Rajapaksa when he fled his official residence was handed over to a court Monday after being turned in by protestors, police said as a succession battle got under way.

Around 17.85 million rupees (about $50,000) in cash Rajapaksa left behind at the presidential palace was handed over to a court after being turned in by protesters, police said.

"This shows what can be done when people decide to exercise their power."

Sri Lanka, once a relatively wealthy economy, is in the throes of an unprecedented crisis with hyperinflation and critical shortages of essentials like food, fuel and medicine.

Protesters have been calling for months for Rajapaksa, part of a powerful clan which has dominated politics for decades, to quit.

Rajapaksa, 73, fled the presidential palace on Saturday using a back entrance under military cover.

This was minutes before tens of thousands of protesters breached the iron gates despite the presence of police with live ammunition, tear gas and water cannon.

On Sunday he was holed up in a navy ship offshore and has said he will resign on Wednesday.