PRAGUE (Reuters) - Czech gymnast Vera Caslavska, whose seven gold medals made her the country's most decorated Olympic athlete, has died aged 74 after a long battle with pancreatic cancer, the head of the Czech Olympic Committee said on Wednesday.

"Vera was a fighter. She was diagnosed last year in the spring... When she did not come with us to (the Olympic Games this summer in) Rio it was clear the situation was bad," committee President Jiri Kejval said by telephone.

"She died in her sleep," he said.

Caslavska's medals included golds in the individual all-round gymnastics in the 1964 and 1968 games. Larisa Latynina is the only other female athlete to win back-to-back gold medals in that event. She won gold in 1956 and 1960 for the Soviet Union.

Caslavska was a vocal critic of the Soviet Union's 1968 invasion of what was then Czechoslovakia and did not compete in the Olympics after that year's games after refusing to withdraw her signature on the "Manifesto of 2000 Words", which rejected Soviet involvement in the country.