THREE young people were missing early this morning after Hongkong was hit by its heaviest storm of the year. An average of 153 millimetres of rain fell - and more is forecast for today. The Royal Observatory said areas in the east of the territory, particularly Sai Kung, were the worst hit with about 280 mm of rainfall recorded. But the downpour also hit hard in the west, with 200 mm falling in Tsuen Wan, mainly between 12.18 pm and 2.50 pm. Twenty-nine reports of landslides and 257 of flooding were received - 160 in the New Territories, 70 in Kowloon, and 27 in Hongkong. The people missing are two boy scouts, aged 19 and 16, and a girl guide, 16, who were camping in the Sai Kung hills. The trio, working for their camping badges, lost contact with their assessor who alerted police at about 5 pm. A helicopter searched hills between Tai Long Wan to Chek Keng in conjunction with police, Civil Aid Services and Mountain Rescue Team members on the ground, but early this morning no trace of the teenagers had been found. They had set out from Tai Long Wan on Sunday and were expected to reach Chek Keng on Tuesday after spending two nights in the hills to win their badges. Their last contact with the assessor was on Monday. The storms saw numerous roads closed because of floods and landslips on both sides of the harbour and also delays at Kai Tak and on the railways. About 500 passengers were stranded on KCR trains, including those on an express from Guangzhou which arrived at Hunghom at 1.43 am today - more than 12 hours later than scheduled. The train left Guangzhou at 10.30 am and was forced to stop near Shenzhen because of a landslide that blocked the track. It was due to arrive at 12.40 pm. A number of flights into Kai Tak were diverted, with several arriving later when conditions had improved. Departing flights were not seriously affected. Flooding was reported in Des Voeux Road Central, the Chai Wan MTR bus station, Wah Fu Estate bus terminus, Victoria Road near Ka Wai Man Road, and the Island Eastern Corridor. Among areas badly hit in Kowloon was Chatham Road. Bus services were also hit, with route suspensions and diversions because of road subsidence, flooding and fallen trees. Landslips were reported at Fu Yung Shan in Tsuen Wan and at Kap Pin Long Village in Sai Kung, and throughout the day people were urged to leave their homes if they were in danger from unstable slopes. The City and New Territories Administration threw open 49 emergency shelters for those affected. All schools, child care services, day rehabilitation and elderly services centres suspended activities, but staff remained to look after those who arrived before the facilities were closed.