High Quality Content by WIKIPEDIA articles! More than 50 different modifications and experimental vehicles based on the T-26 light infantry tank chassis were developed in the USSR in the 1930s, with 23 modifications going into series production. The majority were armoured combat vehicles: flame-throwing tanks, artillery tractors, radio-controlled tanks, combat engineer vehicles, self-propelled guns and armoured transport vehicles. They were developed at the Leningrad Factory of Experimental Mechanical Engineering (from 1935 known as Factory No. 185 named for S.M. Kirov) by talented Soviet engineers P.N. Syachentov, S.A. Ginzburg, L.S. Troyanov, N.V. Tseits, B.A. Andryhevich, M.P. Zigel and others. Many Soviet tank engineers were declared "enemies of the nation" and repressed during Stalin's Great Purge from the middle of the 1930s. As a result work on self-propelled guns and armoured transport vehicles ceased in the USSR during that time. T-26 light tanks were also modified in the field during wartime.