The Hong Kong State Flight Service (GFS) said the ship sank about 300 kilometers or 185 miles southwest of the island.
In a post on her Instagram account, GFS said it received the rescue request at 7:25 a.m. local time on Saturday. It says the ship’s crew abandoned the ship after it sustained significant damage in the South China Sea.
A dramatic video of the rescue operation shows a crew member being roped into the helicopter from the ship as it sinks.
Three crew members were rescued, but the fate of the remaining 27 people on board the ship remains unclear, GFS said, adding that search and rescue efforts are hampered by severe weather conditions.
Four helicopters and two planes were sent to the scene for search and rescue operations, the GFS added.
The storm caused disruptions across the region, with flights canceled and some businesses closed due to high winds and heavy rains.
Hong Kong authorities issued a typhoon warning Thursday during a long-awaited visit by Chinese leader Xi Jinping. The grand opening of Hong Kong’s new Palace Museum, which was supposed to coincide with the 25th anniversary of the city’s handover from British rule to China, was delayed until Sunday due to a storm.
Chaba made landfall in China’s Guangdong province around 3:00 pm local time (3:00 am ET).