Two Indonesian military skydivers have plunged to their deaths during an airshow rehearsal in the country's capital.

Indonesian air force spokesman Air Marshal Dwi Badarmanto said one of the victims fell from about 12,500 feet (3,800 meters) over a residential area close to an air force base on Thursday after his parachute failed to open.

The second skydiver lost control when strong winds disrupted his descent.

Badarmanto said the deaths would be investigated. Both men were members of the air force's elite troops.

They were rehearsing jumps with hundreds of other skydivers for a celebration of the air force's 70th anniversary on Saturday.