The ministry said on Saturday that the helicopter crashed near Belgrade's international airport late Friday while transferring a five-day-old baby for emergency medical treatment.
The helicopter picked up the baby after an ambulance taking the child to hospital for treatment was stuck in a mudslide in central Serbia some 200 kilometers south of the capital, Belgrade.
The MI-17 transport helicopter was carrying four crew members, two medical workers and the baby, who was suffering life-threatening respiratory problems.
The crash occurred in foggy weather, causing several commercial flights to be rerouted to other airports.
The helicopter was awaiting clearance to land when it lost contact with air traffic controllers.
The chopper had tried to make an emergency landing twice due to poor visibility but it had failed.
The military police has sealed off the crash site for an investigation.
The Serbian government declared Sunday a day of mourning. Prime Minister Aleksandar Vucic also offered condolences to the families of the victims.