HAIKOU - South China's island province of Hainan upgraded its emergency response to the highest level on Sunday morning with Typhoon Kajiki approaching.

As of 8 am, the typhoon -- packing winds of up to 38 meters per second, was located about 210 km southeast of the province's resort city of Sanya. It is strengthening and moving toward the southern coast of Hainan, and is forecast to make landfall or pass near the coast on Sunday afternoon or evening.

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Authorities have evacuated a total of 20,728 people from potentially hazardous areas. All 30,769 local fishing boats have returned to port or are sheltering safely -- with over 21,000 crew members moved to the shore.

Hainan has prepared more than 770,000 items of emergency supplies for vulnerable areas. Over 2,800 rescue personnel are on standby and are equipped with vehicles and equipment.

The city of Sanya has implemented a series of measures, halting classes, work, business operations, public transport and shipping, while also closing scenic areas.

Residents are urged to avoid unnecessary travel, stay away from low-lying areas, temporary structures and coastal waves, and to be alert for geological hazards.

READ MORE: South China coastal provinces brace for Typhoon Kajiki

On Sunday, China's National Meteorological Center also issued an orange alert for Typhoon Kajiki, warning of gusts in areas near the typhoon center -- and heavy to torrential rainfall in parts of Hainan, Guangdong and Guangxi, all located in South China.

China has a four-tier emergency response system, with Level I being the most severe response, and a four-tier weather warning system, with red representing the most severe warning, followed by orange, yellow and blue.