Leung Chun-ying on Friday condemned as "political propaganda" a newspaper column that drew an analogy between the chief executive's troubled daughter and his political opponents. In a letter to the Hong Kong Economic Journal , Leung expressed "extreme regret" that a piece by Joseph Lian Yi-zheng, published on Thursday, showed utter disregard to his daughter Chai-yan's health woes. The column appeared two days after Leung pleaded with the media and public to leave Chai-yan alone, as he admitted for the first time that she was receiving medical treatment for unspecified health problems. In his commentary, Lian, a former member of the government's Central Policy Unit think tank, compared Chai-yan to Hongkongers fighting for freedom and said her parents were like a repressive regime. READ MORE: Hong Kong chief executive faces TV debate challenge over reform "As chief executive, I don't mind people expressing different opinions. But people holding different political views should not use the health or emotional problems of family members of public office holders to serve their purpose of political propaganda," Leung wrote, in a letter published by the paper yesterday. "Chai-yan's state of illness is not light and she needs space for recovery," he wrote. "Political attacks should never affect one's family. This is the bottom line for any person. I urge Lian and your newspaper to stop doing this." Chai-yan has been in the spotlight since her father's election in 2012, often for social media posts attacking her father's critics or expressing her own state of mind. On Tuesday, Chai-yan posted that her mother, Regina Leung Tong Ching-yee, had assaulted her. Police and an ambulance were called to Government House, but her father later denied any assault took place. Chief editor Alice Kwok Yim-ming said her paper was simply a "carrier" which published Lian's article, and it was natural to publish Leung's reply. "Lian's views do not represent the stance of the Economic Journal ," she said. Lian, who was involved in a 2013 spat with Leung over a column the chief executive said was defamatory, did not respond to requests for comment yesterday. Veteran journalist and Civic Party lawmaker Claudia Mo Man-ching said it was "unwise and inappropriate" for Leung to attempt to stop media comments on the incident involving his daughter. She said the case involved matters of public interest.