The 27-year-old wheelchair racer, who earned two Paralympic medals in Tokyo last year including gold in the women’s T53 400 metres, twice bettered the world mark in the T53 800 metres.

She clocked 1min 45.53sec in her morning heat, and then won the final in 1:44.87.

"It feels unbelievable to make two world records in one day!" said Debrunner, who also plans to compete in the 100, 200, 400 and 1500 metres racing.

"The 800m is something really special to me.

"I have been dreaming of this world record for many, many years and I knew that the tactic was really risk.

"But I had the courage to do it and in the end I did it and I just feel so incredibly happy - it just feels great."

Athletes from 46 countries are competing over three days on the Swiss track famous for being the home of some of the world’s best wheelchair racers.

Switzerland’s multiple major marathon winners and world and Olympic gold medallists Marcel Hug and Manuela Schär are also competing.

There was a European record for Britain’s James Freeman in the men’s 800m T33 race as he clocked 2:10.64.

Freeman’s compatriot, seven-times Paralympic gold medallist Hannah Cockroft, won the women’s 800m T34 race in 1:50.28.

The women’s 800m T54 title went to Susannah Scaroni of the United States in 1:45.41.         

In men’s track competition, Indonesia’s Saptoyogo Purnomo won the 200m T37 gold in 23.36sec from Germany’s Franz Koalick, who clocked 25.81.

The 200m T51 was a close affair as Finland’s Toni Piispanen clocked 37.11 to beat Roger Habsch of Belgium who recorded 37.87.

The T52 800m was also tight as home athlete Fabian Blum won in 31.87 from Britain’s Marcus Perrineau, who was timed at 32.21.

In the T53, Pierre Fairbank of France won in 26.11, with Saudi Arabia’s Abdulrahmen Alqurashi second in 26.89.

Nathan Maguire of Britain earned the T54 honours by a whisker, 24.67 to 24.90, from Finland’s Leo-Pakka Tahti.