The defence ministry reported that the crash happened "during routine duties" as the self-propelled mobile anti-aircraft system travelled in a convoy with a military police escort.

"According to early reports, there are injured and dead in the accident," the ministry said without providing further details.

Later, the director of Kraljevo General Hospital Zoran Mrvic told state media that five people had died, including three children, and that another person was in serious condition.

The ministry of internal affairs said that a Serbian army driver had been detained on suspicion of causing a traffic accident.

The defence ministry said that an investigation into the incident was ongoing.