A Czech appeals court has sentenced a former top Communist party official to six years in prison for his role in support of the 1968 Soviet-led Warsaw Pact invasion of what was then Czechoslovakia.

The judges in Prague ruled that Karel Hoffmann was guilty of abuse of power for ordering a shutdown of the Czechoslovak Radio on August 21, 1968, as Warsaw Pact tanks rolled into the country. The court said this deprived citizens of information about the Soviet-led invasion.

A lower court had sentenced Hoffmann to four years in prison last June. But the appeals court added another two years to the term.

The invasion crushed the liberal reforms of the so-called Prague Spring instituted under then Czechoslovak Communist Party leader Alexander Dubcek. A hardline Communist regime took over and ruled Czechoslovakia until the 1989 peaceful revolution ended the party's rule in the country.