The Central Academy of Drama stripped singer and actor Tong Zhuo of his graduation certificate on Friday after investigations by local authorities found he had changed his identity during the national college entrance exam, or gaokao.

Three people were put under police investigation and another 12 people have been punished for aiding Tong in fabricating his identity, according to a notice by Shanxi's Linfen Commission for Discipline Inspection of the Communist Party of China and the Linfen Supervisory Commission on Friday.

The scandal broke when the singer was chatting with fans on a livestreaming platform late last month. "We used a lot of so-called guanxi (connections) and then I became a fresh high school graduate," said Tong, 26, laughing with one hand over his mouth.

His cheating at the gaokao soon caused an outcry from netizens demanding an investigation, despite his apology and asking the academy to withdraw his diploma.

According to the investigation results released by the Shanxi provincial education department on Friday, the singer changed his personal information to show he was a fresh high school graduate before he took the gaokao in 2013 for the second time, so he could be eligible for a top art school that only accepts recent graduates.

A separate investigation by Linfen's disciplinary watchdogs found he had the identity changed with the help of his stepfather, Tong Tianfeng, deputy secretary general of the Linfen People's Congress.

Tong Zhuo first took the gaokao in Beijing under the name Li Zhenhua in June 2012 and was not admitted to his dream school, the School of Military Culture at the National Defense University of the People's Liberation Army. He wanted to apply to the school again the next year. However, only fresh high school graduates are eligible to apply.

So, Tong Tianfeng consulted Peng Bo, an education official in Linfen about how to change Tong's personal information.

With help from Peng and a few others in the local education system, Tong Zhuo's identity was changed to a fresh high school graduate in Linfen and he took part in interviews at the School of Military Culture, the Central Academy of Drama and the Tianjin Conservatory of Music in early 2013.

He failed the test at the School of Military Culture again, and applied for the latter two schools in that year's exam. He was later admitted to the Central Academy of Drama.

The Linfen discipline watchdog said on Friday that Tong Tianfeng has been removed from office, and three education officials were put under police custody for allegedly forging documents.

According to the academy, Tong was admitted in 2013 and did not get a diploma from the university when he graduated in 2018, as he did not meet requirements.

Tong said in his apology that he felt guilty. "Public criticism has made me realize my mistake," he said. "The gaokao is a very serious exam and no one should speak or act unlawfully to jeopardize its fairness and justice."