As the powerful storm left the Southeast Asian archipelago and barrelled towards densely populated Hong Kong, Philippine authorities began sending search teams to remote areas hit by communication and power outages, AFP reported Sunday.
The Philippines is routinely hit during the typhoon season but the strength of Manghukt evoked memories of the deadliest storm on national record - Super Typhoon Haiyan - which killed more than 7000 in 2013.
Updates from the Joint Typhoon Warning Center have measured wind speeds of 195mph with higher gusts. It's expected to be 101 nautical miles from Hong Kong by midday local time on Sunday.
Mangkhut's winds weakened to 170 kilometers (105 miles) per hour after the storm blew across Luzon island toward the South China Sea, aiming at southern China and Hong Kong, where residents braced for the worst.
To prepare, the Hong Kong government convened an interdepartmental meeting on Wednesday.
At least 12 people have died after Typhoon Mangkhut caused landslides, ripped off roofs and brought down trees in the Philippines.
A statement from authorities late on Saturday said the decision to shut Macau's 42 casinos was approved by the city leader and agreed by gaming bosses. Members of the public should stay on high alert, and note the impacts of changes in wind direction.
Shops and businesses were boarded up and protected by sandbags across the city and its streets, usually crowded with tourists, were deserted.
The worst of the storm will be borne by Hong Kong and Macau, however, which are now in Mangkhut's path.
A woman weeps as she talks about her family's experience at the height of Super Typhoon Mangkhut in the town of Baggao, Cagayan province on September 15, 2018.
Typhoon Mangkhut has been downgraded from super typhoon status, but is still the strongest storm this year so far, with gusts of up to 200mph.More news: Rain and wind from Hurricane Florence begin lashing United States coast
The Governor of Cagayan, Manuel Maamba said emergency services are clearing debris from main roads.
Wind and rain are preventing government agencies from assessing the full extent of damage, Defence Secretary Delfin Lorenzana said in a televised news conference.
But the storm was unlikely to get any stronger, Rojas said.
Also a young girl was found in the Marikina River in the eastern part of metropolitan Manila, which appeared to avoid major damage. Six transmission lines in Luzon were toppled by the storm. Humanitarian partners have been requested to participate in the coordinated assessments.
Airlines canceled more than 500 flights, disrupting travel from Hong Kong to Japan. Its unit Cathay Dragon said it won't be flying Sunday.
China and the Philippines agreed to postpone a visit by Chinese Foreign Minister Wang Yi that was to start Sunday due to the onslaught, which caused almost 150 flights, a third of them worldwide, to be cancelled and halted sea travel.
AirAsia Group Bhd had cancelled at least 22 flights as of Saturday morning, upsetting travellers from Manila to Shenzhen and Macau, according to a Facebook post.
Philippine Airlines is scrapping 10 worldwide flights on Sunday.
About a quarter of the estimated 4.2 million people affected by the storm live in poverty and the United Nations estimated about 1.4 million farmers and 100,000 fishermen were hit by the typhoon.
Mangkhut, a Thai word for the mangosteen fruit, is the 15th storm this year to batter the Philippines, which is hit by about 20 a year and is considered one of the world's most disaster-prone countries.