A man reported missing after going hiking near Tuen Mun on Sunday has died, police said on Tuesday.

The man, 67, was found by rescue workers near the Tsing Tai Stream at around 6.30am on Tuesday.

He was declared dead after being flown to hospital by helicopter.

Chung Kin-man, a veteran hiker, warned the public about the dangers of hiking alone, especially during hot weather.

"More than 50 or 60 percent of people go hiking by themselves, alone. I think that is a big mistake. We always propose that people should go with some other people, friends or family, together. You may twist your ankle or break your head. It will kill you," he told RTHK.

"The weather, in these few days, is very hot... maybe you just carry a small bottle [of water] and it's not enough. Once you don't have enough water, you lose consciousness, you don't know where you are."

He said people had misconceptions that solo hiking is safe in a place with advanced technology.

"A lot of people nowadays, they go hiking because they're carrying a phone. They think that their phone can help them. But sometimes in the country park, there's no network, sometimes [the phone runs] out of battery," he said.