A parachutists descends into the city center during National Day Parade rehearsal held in Singapore on June 15, 2019. (Photo: Xinhua)

A fighter jet flies at high speed during National Day Parade rehearsal held in Singapore on June 15, 2019. (Photo: Xinhua)

Helicopters fly during National Day Parade rehearsal held in Singapore on June 15, 2019. (Photo: Xinhua)