Leung is under a 'supervision order' requiring him to delete his social media account and not talk to the media.
By Tong Syu Yuet and Gao Feng
Hong Kong independence activist Edward Leung is shown in a file photo.
Edward Leung, a prominent Hong Kong politician who advocated "separation" between the former British colony and mainland China, has been released at the end of a six-year jail term for "rioting" during 2016 unrest in Mong Kok.
A former spokesman for the now-disbanded group Hong Kong Indigenous, Leung was released from Shek Pik prison on Lantau Island at around 3.00 a.m. on Wednesday.
"I was released this morning and am back home safe with my family," Leung said in a post to his Facebook page.
"As required by law, I am subject to a supervision order upon release," he wrote. "I must keep a low profile and deactivate my social media accounts."
His family later posted a warning to supporters not to try to visit Leung, and announced the deletion of Leung's Facebook account, which was unavailable on Wednesday evening local time.
Leung was sentenced to six years in prison in 2018 for "rioting" and "assaulting a police officer" during the 2016 "Fishball Revolution" clashes in Mong Kok.
Hong Kong barrister and former lawmaker Siu Tsz-man said supervision orders are sometimes issued to released prisoners involved in violent crimes, including murder and manslaughter, and require the former prisoner to maintain contact with supervision officers and remain at a stable residence.
But Siu said the order to stay away from the spotlight was unprecedented.
"I have never heard of this happening before," Siu said. "My staff have never heard of a supervision order under which the person isn't allowed to give interviews to the media."
Siu declined to comment on whether the order was appropriate without knowing the details of the case.
"The point of a supervision order isn't to confine someone at a certain location and not let them leave," he said.
Some drew parallels between Leung's release and the continuing controls on released political prisoners in mainland China.
Hong Kong current affairs commentator Johnny Lau said the treatment of prominent Chinese dissidents has varied greatly in the past, depending on the level of political sensitivity of their cases, as viewed by the ruling Chinese Communist Party (CCP).
Mainland Chinese rights lawyer Wang Yu said the mainland Chinese authorities often negotiate terms with released dissidents, including telling them to stay quiet after their release.
"This can be done through the detention center, through the courts, or the local police department or state security police, or even neighborhood committees," Wang told RFA. "Anyone can be pressed into service as a stability maintenance officer."
"These deals may or may not involve something in writing."
Fellow rights attorney Bao Longjun said Leung's experience shows that Hong Kong has gradually moved away from the rule of law.
"The Hong Kong government's continual expansion of the way it interprets and implements [existing laws] has seriously violated the rule of law and the interpretation of the freedom of speech as granted by the constitution," Bao told RFA.
Video footage of the riots showed a large crowd throwing bricks and other objects at riot police, who fought back with pepper spray and batons, injuring an unknown number of people. Others set fire to debris in the street, while business owners reported damage to property.
Judge Anthea Pang said while passing sentence that "political pleas" could never justify violence. Leung, a by-election candidate for the localist group Hong Kong Indigenous at the time, said he went to the scene to try to act as a buffer zone in the clashes, but later admitted giving in to anger.
Former colonial Hong Kong governor Lord Patten of Barnes criticized Leung's sentence as politically motivated at the time, saying public order legislation was being used politically under CCP rule to hand out extreme sentences to democratic politicians and other activists.
Translated and edited by Luisetta Mudie.