Liang, who had never raced a distance more than 35km before, clocked 4 hours 4min 36sec to win the most competitive women's race ever held over the distance.

Portugal's Ines Henriques, who set the previous record of 4:05:56 in winning the inaugural world title in London last year, was the pre-race favourite but dropped-out at 29km to leave a four-strong lead pack.

Australia's Claire Tallent, another 50km debutant, attempted to attack but was reeled back in by a Liang-led Chinese trio.

Liang then broke clear herself and moved two minutes ahead of team-mates Li Maocuo and world silver medallist Yin Hang.

Yin held on for second place in 4:09:09 as Tallent recovered to take bronze just 24 seconds further back.

Li faded to seventh out of 29 finishers in a race which may go a long way in helping the event's ambitions to be added to the Olympic programme.

"I chose to follow the others at the start to save my energy and then waited for the right moment to break away," said Liang. 

"It was after passing 40km that I realised I could break the world record. 

"At that time I felt I still had energy in reserve and could speed up further."

China also won the team gold with eight points ahead of Ecuador in second with 21 and Ukraine in third with 40.

Maria Gonzalez became the first woman in history to successfully defend the 20km title at the World Race Walking Team Championships.

The Mexican timed her effort superbly to triumph in 1:26:38.

Home Chinese athletes thrived again to take both minor medals.

Shijie Qieyang crossed second in 1:27:06 while Jiayu Yang was third another 16 seconds back.

China won another team title with 17 points in comparison with 38 for second placed Italy and 40 for third placed Spain.

Japan had never won a medal of any colour in the men's 50km races at the event - but swept the top three positions today.

It came in a wide open race in the absence of 2016 champion Jared Tallent - Claire's husband - France's world champion Yohann Diniz and Slovakia's Olympic champion Matej Toth.

World silver and Olympic bronze medallist Hirooki Arai won in 3:44:25.

Hayoto Katsuki and Satoshi Maruo finished six and 27 seconds behind the winner respectively in second and third.

Japan took the team title with a best possible haul of six points.

Ukraine took second with 29 and Poland third with 37.

The men's 20km race will be held tomorrow.