Franciszek Andrzej Mazur (born Lewko Horodenko), also known as Stanisław Gajsler[1] (August 1, 1895 – March 7, 1975) was a Polish lawyer of Ukrainian descent, a communist politician.

After the February Revolution and the overthrow of the tsar, while serving in the navy in Sevastopol in 1917, he joined the Polish Socialist Party - Left and collaborated with the Bolsheviks.

Then, in the years 1928–1930, he was the head of the department of higher and vocational schools in the People's Commissariat of Education of the Ukrainian SSR (1928-1930), and finally the first secretary of the Regional Committee of the WKP(b) Shepetówka-Berdyczów (1930).

At the same time, from June 15, 1930, to January 18, 1934, he was formally a deputy member of the Central Committee of the Communist Party (Bolsheviks) of Ukraine.

He served his sentence in prisons in Lviv, Rawicz, Wronki and Koronowo, then emigrated to Czechoslovakia and France.

On March 15, 1941, he was sentenced to five years in a labor camp for anti-Soviet propaganda - in conversations in the prison commune in Koronowo in 1937, he was supposed to negate the counter-revolutionary nature of Trotskyism and support the Trotskyists during his activities in the 1920s in Ukraine.

[citation needed] He was buried on March 11, 1975, with honors in the Aleja Zasłużonych at the Powązki Military Cemetery in Warsaw.