Rescuers in Malaysia are trying to trace six pupils and two teachers missing since Friday's earthquake hit the highest peak, Mount Kinabalu.
The body of a 12-year-old girl from their school, in Singapore, has been recovered, Singapore's ministry of education said.
Officials say at least 13 people died in the earthquake, which brought rocks tumbling down the mountain.
More than 130 people stranded on the peak made it to safety.
The schoolgirl whose body was recovered was named by Singapore as Wee Ying Ping Peony from Tanjong Katong Primary School.
She was among more than 30 pupils and teachers, on an educational trip, caught up in the 6.0-magnitude quake in the Malaysian state of Sabah on Borneo island.
A boy, 12, from the same school was rescued and is receiving medical treatment in Kota Kinabalu.
A Malaysian guide was also one of those killed.
Earlier, the Sabah Tourism Minister Masidi Manjun tweeted: "The 137 climbers have safely arrived at the Park HQ, the last batch at 02:50 (18:50 GMT on Friday)."
Reports say those climbing at the time included nationals from China, the United States, the Philippines, the UK, Thailand, Turkey, and Japan.
The earthquake was so powerful it also snapped off one of Mount Kinabalu's "Donkey's Ear" peaks, Mr Manjun added.
Bad weather hampered rescue efforts on Friday, preventing helicopters from landing on the mountain. Many of the climbers had to make their own way down with the help of tour guides and park rangers.
Some of the group had climbed to the summit to watch the sunrise as the earthquake struck.
The US Geological Survey said the quake happened at around 07:15 local time (23:15 GMT), at a depth of 10km (32,800ft). The epicentre was 54km (33 miles) from Mount Kinabalu, which stands at 4,095m.
The quake also damaged roads and buildings, including schools and a hospital on Sabah's west coast.
Many climbers are attracted to the challenging "via ferrata" climbing route, where cables, metal rungs and bridges are set into the rocks on the steep terrain to help people ascend.
All activity on the mountain has now been suspended.
Climbing Mt Kinabalu
- Climbing up and down Mt Kinabalu takes on average two days and one night. There are two trails - the Summit trail and the more advanced Mesilau trail
- The Summit trail begins at Timpohon Gate (1,800m; 5,906 ft)
- It takes about 6-8 hours to reach Laban Rata (3,273m; 10,738 ft) where climbers rest for a few hours
- They usually depart for the summit at 02:00 in the morning, reaching it 4-5 hours later before descending the mountain
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