Sri Lanka president flees his country on a military aircraft

Gotabaya Rajapaksa had promised at the weekend to resign on Wednesday and clear the way for a "peaceful transition of power", after fleeing his official residence in Colombo just before tens of thousands of protesters overran it.

As president, Rajapaksa enjoys immunity from arrest, and he is believed to have wanted to go abroad before stepping down to avoid the possibility of being detained.

He, his wife and a bodyguard were among four passengers on board an Antonov-32 military aircraft which took off from the main international airport heading for the neighbouring Maldives, according to immigration sources.

"Their passports were stamped and they boarded the special air force flight," an immigration official involved in the process told AFP.

The departure of the 73-year-old leader once known as 'The Terminator' had been stymied for more than 24 hours in a humiliating stand-off with immigration personnel at the airport.

He had wanted to fly to Dubai on a commercial flight, but staff at Bandaranaike International withdrew from VIP services and insisted that all passengers had to go through public counters.

The presidential party were reluctant to go through regular channels fearing public reactions, a security official said, and as a result missed four flights on Monday that could have taken them to the United Arab Emirates.

Clearance for a military flight to land in the closest neighbour India was not immediately secured, a security official said, and at one point on Tuesday the group headed to a naval base with a view to fleeing by sea.

Rajapaksa's youngest brother Basil, who resigned in April as finance minister, missed his own Emirates flight to Dubai early Tuesday after a tense standoff of his own with airport staff.

Basil -- who holds US citizenship in addition to Sri Lankan nationality -- tried to use a paid concierge service for business travellers, but airport and immigration staff said they had withdrawn from the fast track service.