A passenger flight headed to Faro, Portugal, took off from Brussels Airport on Sunday, the first passenger flight to depart from the airport 12 days after suicide bombings killed more than 30 people in the Belgian capital.

According to the airport's website, flights to Turin and Athens were also due to take off later in the day, with a longer list of departing flights scheduled for Monday.

The three flights were a test run for a European aviation hub that used to handle 600 flights a day and plans to slowly climb back to normal capacity.

Security at the airport was tight with new check-in procedures for passengers in temporary structures.

Arnaud Feist, the CEO of Brussels Airport, said that Belgium's biggest airport would gradually climb to 20 percent of capacity in the coming days, able to process 800 passengers an hour - maximum capacity for the temporary structures.

The airport has been closed since March 22, after suicide bombings hit the airport's departure hall and a Brussels subway train, killing 32 people and wounding 270.

Damage is seen inside the departure terminal following the March 22, 2016 bombing at the airport [AP]

Feist said at a Saturday news conference that the three flights were a "sign of hope" following "the darkest days in the history of aviation in Belgium".

On Sunday, he thanked employees for their courage, solidarity and the "impressive work carried out in so little time".

"We are more than an airport ... We are a family more bound together than ever," he said at a ceremony at the airport.

The attacks, in which three suicide bombers also died, were claimed by the Islamic State of Iraq and the Levant group.

Since then, new security measures have been ordered at the airport, including spot checks of vehicles before they arrive and the closing of a drop-off parking area outside the terminal, according to Belgian Federal Police spokesman Michael Jonniaux.

Belgian soldiers control the access to the airport [Reuters]

He said that all passengers would be screened along with their travel documents and baggage before they were allowed to enter the facility.

The bombers entered the airport's check-in area with suitcases packed with high explosives and nails, and the resulting blasts caused the ceiling to collapse, shattered windows and caused massive damage.

There will be no access by rail or public transport to the airport for the foreseeable future, the airport CEO said.

Brussels Airport served about 1.5 million people in February, the month preceding the attack. Feist said he hoped full service could be restored by the end of June or the beginning of July, in time for the summer holiday season.

Source: Agencies