Political prisoner Mikalai Statkevich wrote his brother, who lives in Ukraine, about protests in Kyiv and the relations between Ukraine and Russia.
But the letter didn't leave the prison in Mahilou, where the former presidential candidate serves his term.
Radio Svaboda learnt it from Maryna Adamovich, the wife of the political prisoner.
"He wrote me that he had sent a letter to his brother about the pro-EU protests and possible results of Moscow's attempt to measure wallets with the EU for Ukraine. But the letter didn't pass the prison censorship," the political prisoner's wife said.
Maryna Adamovich says Mikalai wrote in the latest letter he had spent three years in prison, the half of the sentence. "He wrote the time had passed quickly," Maryna Adamovich says.
Mikalai Statkevich was sentenced to 6 years in prison allegedly for organising disorders on December 19, 2010.