Things are very bad in socialist Venezuela and getting worse by the day, see Socialism Taken to the Next Level: Venezuela's New Decree Forces Farm Work On Citizens.
But it doesn't come close to what occurred on Mao's communist China.
From Frank Dikötter’s short note at History Today:
In the People’s Republic of China, archives do not belong to the people, they belong to the Communist Party. They are often housed in a special building on the local party committee premises, which are generally set among lush and lovingly manicured grounds guarded by military personnel. Access would have been unthinkable until a decade or so ago, but over the past few years a quiet revolution has been taking place, as increasing quantities of documents older than 30 years have become available for consultation to professional historians armed with a letter of recommendation. The extent and quality of the material varies from place to place, but there is enough to transform our understanding of the Maoist era.
…What comes out of this massive and detailed dossier is a tale of horror in which Mao emerges as one of the greatest mass murderers in history, responsible for the deaths of at least 45 million people between 1958 and 1962. It is not merely the extent of the catastrophe that dwarfs earlier estimates, but also the manner in which many people died: between two and three million victims were tortured to death or summarily killed, often for the slightest infraction. When a boy stole a handful of grain in a Hunan village, local boss Xiong Dechang forced his father to bury him alive. The father died of grief a few days later. The case of Wang Ziyou was reported to the central leadership: one of his ears was chopped off, his legs were tied with iron wire, a ten kilogram stone was dropped on his back and then he was branded with a sizzling tool – punishment for digging up a potato.
…Fresh evidence is also being unearthed on the land reform that transformed the countryside in the early 1950s. In many villages there were no ‘landlords’ set against ‘poor peasants’ but, rather, closely knit communities that jealously protected their land from the prying eyes of outsiders – the state in particular. By implicating everybody in ‘accusation meetings’ – during which village leaders were humiliated, tortured and executed while their land and other assets were redistributed to party activists recruited from local thugs and paupers – the communists turned the power structure upside down. Liu Shaoqi, the party’s second-in-command, had a hard time reining in the violence, as a missive from the Hebei archives shows: ‘When it comes to the ways in which people are killed, some are buried alive, some are executed, some are cut to pieces, and among those who are strangled or mangled to death, some of the bodies are hung from trees or doors.’
( Dikötter’s via Tyler Cowen)