Wreaths were laid by delegations of the President of the Republic, the Parliament, the Ministry of Family Affairs, War Veterans and Intergenerational Solidarity, the Association of Civilian Victims of the Homeland War, and political parties.
Serb rebels fired missiles at Zagreb on May 2 and 3, 1995, killing six civilians and wounding 175, of whom 39 seriously.
The attack began at 1023 hours on May 2 when several missiles filled with cluster munitions, popularly known as "bomblets", landed on the city centre. The shelling resumed the next day, with missiles hitting a children's hospital, an old people's home and the National Theatre.
Police defused about 500 bomblets, and one police officer was killed in the process.
The attacks were carried out in retaliation for the military defeat inflicted the day before by Croatian army and police forces in a 36-hour lightning offensive codenamed Operation Flash.
The Hague war crimes tribunal charged Serb rebel leader Milan Martic with crimes against humanity and violations of the laws and customs of war for ordering the attacks on Zagreb. Martic has been in the tribunal's custody since May 15, 2002.