The Sudetenland native was among the top performers in the 1970s, winning six World Championships medals including two gold.

At the 1974 World Championships in Falun, Sweden, Grimmer won the title in the 50 kilometres race and was part of the 4x10km relay squad that triumphed.

He finished the 50km race in 2hour 19min and 45.26sec, almost two minutes ahead of Stanislav Henych of Czechoslovakia.

"I was in the leading group for the first 20 kilometres, then I pulled away and my lead grew to over two minutes," said Grimmer on his victory as quoted by Münchner Merkur.

"So I was able to run safely to some extent."

He also added an individual silver in the 15km race in the Swedish city.

Prior to that, Grimmer won two world medals - two silver and one bronze - in Vysoké Tatry.

He was the only German individual world champion in cross-country skiing until Axel Teichmann triumphed in the 15km in Val di Fiemme in 2003.

Grimmer competed in three Winter Olympics Games from 1968 in Grenoble to 1972 in Sapporo and 1976 in Innsbruck, but never managed to win a medal.

Grimmer is also a 17-time German Democratic Republic (GDR) Championship winner.

In 1975, he was awarded the Holmenkollen medal, Norwegian skiing's highest award for competitors.

He worked as an official after retiring and has been accused of being part of the state-sponsored doping programme.

However, the former skier has denied claims despite Stasi documents saying he was aware of the doping practices.