Hong Kong was braced for Mangkhut, with authorities expected to raise the second strongest typhoon signal between 11pm and 2am (1500 and 1800 GMT).
On Sunday morning, the typhoon packed sustained winds of 155 km/h and gusts of up to 190 km/h.
Rain and strong winds lashed Hong Kong Sunday morning as the storm approached. All high-speed and some normal rail services in Guangdong and Hainan provinces were also halted, the China Railway Guangzhou Group Co. said.
The typhoon is continuing on its path, with hundreds of thousands evacuating across China and Hong Kong in preparation.
Images have revealed collapsed building scaffolding and trees bending in the strong winds across Guangdong province.
The Hong Kong government said Mangkhut will pose "a severe threat to the region" as many residents in the city and neighbouring Macau stocked up on food and supplies.
Hong Kong officials have called on residents to prepare for the worst and are urging them to stay indoors.
Tuguegarao's airport damaged due to strong winds in Cagayan province, northeastern Philippines on September 16, 2018. Airlines such as its flagship carrier, Cathay Pacific, cancelled many flights last week.
The New York Times reported that for the first time ever, Macau, the Asian gambling capital nearby, closed its casinos because of a storm.
The government and casinos are taking extra precautions after Macau was battered by Typhoon Hato previous year, which left 12 dead.More news: Right-Wing Anti-Immigration Party Notches Best Showing Ever in Sweden
Water levels surged 3.5 meters (12 feet) in some places, waves swamped roads and washed up live fish, washing into some residential blocks and a mall in an eastern district.
Between 40 and 50 people were thought to be inside the bunkhouse when the landslide occurred and another 32 people were reported dead in separate incidents in Itogon, he added.
Provincial authorities said they evacuated a total of 2.37 million people and ordered tens of thousands of fishing boats back to port before the arrival of what Chinese media has dubbed the "King of Storms".
On Saturday, it plowed into the Philippines, flattening homes in small towns and villages on the northern island of Luzon.
Palangdan said the area where the bunkhouse was located was "dangerous because there was a big tunnel mined" by a private corporation decades ago, blaming mining for the landslides that hit the town of almost 60,000 people.
Tacio, who was at the scene of the landslide earlier Sunday, says rescuers found another man but could not immediately pluck his body, which was pinned by rocks and mud.
Authorities issued a red alert in Hong Kong and southern China as strong winds and heavy rains from Typhoon Mangkhut ripped through dense coastal cities, blowing out windows and flooding hotel lobbies, after it left at least 30 dead in the northern Philippines. At least 29 people have died in the Philippines, with that number expected to rise when rural areas are assessed.
Two rescue workers were killed while trying to free people trapped in a landslide in the mountainous Cordillera region, said Ricardo Jalad, head of the nation's disaster agency.