Starting from the late 1920s with a centrally planned economy, Ukraine was involved in Soviet industrialisation and the republic's industrial output quadrupled during the 1930s. The peasantry suffered from the programme of collectivisation of agriculture which began during and was part of the first five-year plan and was enforced by regular troops and secret police. Those who resisted were arrested and deported and agricultural productivity greatly declined. As members of the collective farms were sometimes not allowed to receive any grain until unrealistic quotas were met, millions starved to death in a famine known as the Holodomor or the "Great Famine".