Thousands of travellers queued cheek by jowl at an airport terminal in the Indonesian capital Jakarta on Thursday, ignoring regulations on social distancing and despite an official lockdown slated to run until the start of June.

Photographs posted on social media, days after the government announced that several airlines could conditionally resume operations, showed passengers queuing to enter the airport and crowding inside the terminal.

One traveller, who asked to remain anonymous, said that confusion reigned as officials attempted to ensure all airline passengers underwent health checks and get flight approval letters stamped.

"Once I entered terminal 2E, there was no clarity," said the 27-year-old, who was travelling for work, one of the designated travel exceptions. "The crowd even reached to the entrance door without any physical distancing measure implemented."

According to guidelines issued by the transportation ministry, airport operators are required to implement health protocols such as temperature checks and manage physical distancing to avoid crowds and queues.

In a statement, state airport operator Angkasa Pura said lines had thinned by afternoon and efforts were underway to ensure physical distancing.

But the scenes have raised fears that the coronavirus is not being sufficiently contained.

"This is worrying because people can take this virus to the regions, especially to villages and this will prolong our misery and our fight against COVID-19," said Alvin Lie of the ombudsman office, which investigates complaints about government agencies.

Despite social restrictions and a ban on the annual visit home by millions of Indonesians at the end of the Muslim fasting month, the government announced last week that migrant workers returning home and people in select industries could fly.

The Islamic holy month of Ramadan ends on May 23 with the Eid al-Fitr festival.

The transport ministry’s director general of aviation said airlines would be sanctioned if they flouted social distancing rules, or exceeded seating capacity limitations of 50% on flights.

Travellers are required to provide a clean bill of health, and a letter from their employer stating the purpose of travel to be able to board an airplane.

Health experts have described the moves as risky and premature, coming at a time that Indonesia’s coronavirus caseload continues to rise.

On Thursday, the Southeast Asian nation reported 568 new infections, taking the total number to 16,006.