Sighting in Hong Kong SARAt around 24:30hrs over a partly cloudy sky along the top of Victoria Harbour sky, I spotted a formation moving from east to west over period of approx. 1/2 hr. The formation is wave like shape with many small lights within the formation. The formation moved forth and back in a westerly direction. The formation flipped around each time as it moved back and forth. However, each time when it flipped, I couldn't tell its exact shape. As the formation moved over Exchange Square, my view was blocked. However, in a matter of minute, I noticed the formation moved high up above the Exchange Square. As it moved high up into the sky, the formation broke out into smaller crafts of different shapes...some in sort of triangular, and some round.... The lights from each craft also lessen somewhat. The crafts flew into opposite directions of each other and disappeared into the sky at speed.I am an investment banker working at a Chinese Bank in a ((deleted)) Director level heading off the ((deleted)) Dept. I hold ((graduate degree)) in ((deleted)) University in the States.