BEIJING — Sun Dawu, one of China's best-known rural entrepreneurs, was handed an 18-year prison sentence on Tuesday, amid broader efforts by authorities in China to rein in powerful businessmen and limit the influence of private enterprise.The billionaire pig farmer was found guilty of eight charges by the Gaobeidian District People's Court in Hebei province. The charges included gathering crowds to attack state agencies, illegal fundraising and "provoking trouble."Nineteen of Sun's relatives and employees were given shorter sentences, ranging from 15 months to 12 years. Sun's Dawu Agricultural and Animal Husbandry Group conglomerate was fined $480,000.Sun's legal team declined to comment on the case, saying it was too politically sensitive. One lawyer said they feared losing their license to practice law if interviewed by NPR.Sun's case stemmed from a minor property dispute with a neighboring state farm that turned violent last summer. Dawu Group employees tried to petition local regulators for help in resolving the dispute. But last November, authorities detained more than two dozen of Sun's relatives and employees, holding them in a type of secret house arrest for more than five months until they were formally charged.They described brutal conditions. "There were no windows in the designated residential surveillance area and the lights were on 24 hours a day, making it impossible to distinguish between day and night," said Jin Fengyu, Dawu Group's deputy director, according to notes provided by Sun's defense team. "A camera watched me and because of the lack of privacy, I never once could bathe."It has not been a good year for private businesses in China. The country's most valuable technology companies are facing a raft of new regulations severely restricting their scope of business. Meanwhile, thousands of owners of small and mid-sized private businesses have been nabbed in a three-year anti-corruption campaign which legal experts say has ensnared many innocent firms.Sun, a 67-year-old social justice advocate and staunch defender of rural development, had once enjoyed a kind political celebrity. Prestigious Chinese universities invited him to deliver lectures on rural land reform and entrepreneurship. Intellectuals and political activists frequently stopped by his company headquarters. Top political leaders sought his advice on raising rural incomes. Over the years, he also covered legal costs for prominent human rights lawyers.The tycoon's idealism spurred him to fund his own hospital and school system, providing heavily subsidized services to Dawu Group's approximately 9,000 employees and their families.Those social services became the basis for one of the charges against him, of illegal fundraising. Authorities said Dawu Group had borrowed $104 billion from employees and relatives on a fraudulent basis since 2003. Sun denied the charge.Dawu Group did not have ready access to credit, highlighting the legal complexities facing rural entrepreneurs. China's ruling Communist Party does not allow the sale of rural land or its use as collateral when obtaining bank loans, forcing rural firms to turn to shadow lending or private wealth.Last year, the state took over Dawu Group's operations, and most of the group's executives are now in prison.During Sun's 12-day trial this month, police repeatedly blocked journalists from attending. Few onlookers were allowed access to the courtroom, despite prior assurances that relatives and employees could attend.Locked out of the court, some employees quietly celebrated Sun's birthday, which, according to the lunar calendar, fell on July 15 — the same day his trial began.Amy Cheng contributed research from Beijing. Copyright 2021 NPR. To see more, visit https://www.npr.org.