President Stjepan Mesic Parliament Speaker Vladimir Seks, Prime Minister Ivo Sanader and numerous ministers, party and other officials attended the ceremony commemorating to commemorate the Vukovar tragedy.
Participants in the commemorations then proceeded in a column through the streets of Vukovar towards the town cemetery, where state and other delegations laid wreaths and lit candles.
After the wreath-laying ceremonies, a requiem mass for those who were killed or went missing in the war was held by Zagreb Archbishop Josip Bozanic.
According to Vukovar officials, some 20.000 people from all over Croatia are expected to take part in the commemorations.
The event will be covered by more than 100 reporters.
The marking of the 15th anniversary of the Vukovar tragedy, which this year is being held under the slogan "Pilgrimage to Croatia's Freedom?", started this morning with a commemoration in front of the town hospital.
The battle of Vukovar started on 25 August 1991. Some 1,800 Croatian soldiers fought back much stronger enemy troops for three months, until 18 November, when the defence lines were broken. During the siege some 15,000 people lived in the town, which was hit by 8,000-9,000 shells every day. According to data from the town hospital, 1,642 people were killed and 2,557 wounded in the attacks, while 22,000 Croats and other non-Serbs were sent into exile after the fall of the town.
Five hundred and ten people from Vukovar-Srijem County are still listed as missing.
The International Criminal Tribunal for the former Yugoslavia indicted former Yugoslav Army commenters Veselin Sljivancanin, Mile Mrksic and Miroslav Radic for the destruction of Vukovar.