A group photo of the Hebei Handan underwater hockey team taken on May 6, 2015.[Photo by Hao Qunying/Asianewsphoto]

Under the calm water, a group of people with simple diving equipment are holding hockey sticks, passing the ball and shooting.

They surface only when they need to take a breath. Due to the need for holding one's breath for extended periods of time, underwater hockey requires strong physical and psychological support.

It's not just hockey - it's an extreme sport. In China, a growing number of people have been joining this sport.

In the summer of 2013, Meng Tao established an underwater hockey club in Handan city, north China's Hebei Province, and membership now exceeds 600. He says his first encounter with underwater hockey came from diving. After hearing news about the first China Cup Underwater Hockey Championship match in Beijing on May 9, 2015, Meng said he started to think of building a team to participate.

Meng's idea quickly got support among the underwater hockey enthusiasts, and the first underwater hockey team in Hebei province was established within only a few days.

Among the 24 team members, people come from different occupations including teacher, policeman, hairdresser etc. What brings them together is their enthusiasm for diving.

In the swimming pool in Handan city, where the players have been training, a group of people with an average age of 30 will jump into the water and quickly dive to the bottom of the pool. Each person holds a stick, and with great effort chases a ball on the pool bottom. From time to time, participants rise to the surface to take a long breath and dives down again to continue the battle.

As underwater hockey requires smaller sticks and a heavier ball, and the game is a newly-developed sport, finding proper equipment to play the game is a major problem. The game has popularity in some foreign countries, so Meng asks friends abroad to purchase the equipment for the team.

Meng says despite the team being established for only three months, the players want to take part in the championship to learn from other teams and enjoy the camaraderie among their fellow underwater-hockey players.