The No 10 typhoon warning is raised in Hong Kong Sunday morning. [Photo by Edmond Tang / China Daily ]

The Hong Kong Observatory issued Hurricane Signal No 10 at 9:40 am on Sunday, as typhoon Mangkhut whipped up winds of up to 118 kilometers.

The observatory said the Hurricane Signal No 10 would remain in force for a few hours. Its forecast showed that Mangkhut would be closest to the Pearl River Delta around Sunday noon, skating about 100 kilometers to the south of Hong Kong.

At 10 am, Mangkhut entered about 150 kilometers south-southeast of Hong Kong.

At 10:55 am, the Observatory raised the rainstorm warning level from amber to red. An Amber Rainstorm Warning Signal, issued at 9:10 am, is the least severe level in the city's three-tier rainstorm warning system, followed by red and black.

The MTR Corporation is providing limited services in underground sections until the end of the operation hours. All services in open, or above-ground, sections, including the Airport Express, have been suspended.

Signal No 10 Super Typhoon Mangkhut wreaks havoc near Heng Fa Chuen, a private residential estate in Eastern District, Hong Kong Island. [Photo by Roy Liu / China Daily]

As of 10 am, a total of 889 flights have been cancelled on Sunday, the Hong Kong Airport Authority said.

Tram, Peak Tram and ferry services were also suspended.

The Home Affairs Department has opened 48 temporary shelters in various districts and 606 people have sought help at the shelters.

In Macao, the meteorology department said it will issue Signal No 10 at 11 am. There, a red storm surge waning is in force.