Zhang Shaojie in an undated photo. (China Aid)

A popular Chinese pastor serving a 12-year jail sentence has been tortured in prison and is reportedly close to death.

Pastor Zhang Shaojie of Nanle County Church in Henan Province is “barely alive”, according to his daughter, Esther Zhang Huixin.

She told the US-based rights charity China Aid he is suffering both mentally and physically as a result of meagre food rations and sleep deprivation.

“They cruelly torture my father,” said Ms Zhang, who is based in the US. “He’s unable to see the sun during the day. He’s deprived of sleep for 24 hours at a time. The prison gives him only one steamed bun a day and intentionally starves him. According to people who have been released from that prison, my father is barely alive, suffering both mentally and physically.”

Zhang Shaojie’s sister, Zhang Cuijuan, reported after recently visiting her brother in prison: “He was in a terrible mental state. His eyes burned from sleep deprivation. He said that he is forbidden to sleep during ‘strict supervision.’ He was depressed, and I had no way to help him. The prison guard held the phone throughout our entire conversation and we were forbidden to talk about his case.”

Pastor Zhang’s daughter suggested that prison officers were carrying out regular torture to persuade him to drop an appeal against his sentence.

“The government officials said that they would not process the appeal unless he would plead guilty,” she said.

Pastor Zhang was sentenced in summer 2014 and fined 100,000 Chinese Yuan ($14,750) for fraud and for “gathering a crowd to disturb public order”. At the time, his family told Sky News the charges had been fabricated by the local authorities, because they were concerned by the growing influence of the Church in the area.

In November 2013 Zhang and around 20 members of his church – which is registered under the state-sanctioned Three-Self Patriotic Movement (TSPM) – were detained after petitioning Beijing over a land dispute between the church and Nanle County officials.

According to the UK-based rights group Christian Solidarity Worldwide, some church members believe their pastor was detained as part of a plan by the authorities to replace him as the head of the local TSPM, because he stood up for marginalised social groups.