Belgium is marking the first anniversary of an attack by religious extremists on Brussels' transport network that killed 32 people.
King Philippe, Queen Mathilde and Prime Minister Charles Michel led a service at the Belgian capital's airport, where 16 people were killed in suicide bomb attacks on March 22, 2016.
Commemorations were also taking place at Maalbeek subway station, where another 16 people were killed by a suicide bomber. A memorial is to be unveiled in the Belgian capital's European quarter.
Some 300 people were injured in the attacks, which the Islamic State militant group (ISIS) claimed responsibility for.
Along with twin attacks on Paris in 2015 and several smaller-scale incidents in Germany during 2016, the attacks helped to highlight the renewed threat to continental Europe from radical Islamism.
