Colombo and Singapore: Sri Lankan president Gotabaya Rajapaksa has submitted a letter of resignation, two government sources said on Friday, after he fled to Singapore following mass protests over his country’s economic meltdown.

Rajapaksa emailed a letter of resignation to the speaker of the country’s parliament late on Thursday, two sources said.

It was not immediately clear if the letter, sent shortly after Rajapaksa arrived in Singapore, would be accepted in email form, the sources added.

In commercial capital Colombo, troops patrolled the streets to enforce a curfew.

Rajapaksa, who fled to the Maldives on Wednesday to escape a popular uprising over his family’s role in a crippling economic crisis, headed on to Singapore on a Saudi Arabian airline flight, according to a person familiar with the situation.

A passenger on the flight, who declined to be named, told Reuters that Rajapaksa was met by a group of security guards and was seen leaving the airport VIP area in a convoy of black vehicles.

Airline staff on the flight told Reuters the president, dressed in black, flew business class with his wife and two bodyguards, describing him as “quiet” and “friendly”.

Singapore’s foreign ministry said Rajapaksa had entered the country on a private visit, and had not sought or been granted asylum.

His decision on Wednesday to make his ally Prime Minister Ranil Wickremesinghe the acting president triggered more protests, with demonstrators storming parliament and the premier’s office demanding that he quit too.