On this day 13 years ago, NATO's war planes attacked a Niš Express bus traveling on a road near the village of Lužane, close to the town of Podujevo in Kosovo.
Some 40 people, many of whom women and children, died in the attack.
Zorica and Dragiša Petrović, Serbs from the enclave of Gračanica in Kosovo, lost two children in the bombing - daughter Maja and son Nikola. Dragiša's mother was also among the victims.
Zorica Petrović still struggles to cope with the loss of her children - she was taken ill after the tragedy and is still receiving therapy on a daily basis.
The three members of the Petrović family were laid to rest on May 7, 1999 - Nikola's 17th birthday.
The Petrovićs spoke to reporters on this day to say that they did not expect to receive any assistance from any quarter, "aware that they are not the only ones to have lost their loved ones during the NATO bombing".
The reason they publicly addressed the tragedy, the family said, was their desire "for someone to have them in their thoughts on this day, and ease their pain and suffering".
NATO launched its war against Serbia on March 24, 1999, and continued with aerial attacks for the next 78 days.