Wong, arguably Hong Kong's best known activist, is already in jail after he was booked under the newly implemented national security law.

He pleaded guilty last Friday, along with fellow activists Lester Shum, Tiffany Yuen and Jannelle Leung.

Wong has been sentenced to 13 and a half months and four months in prison on two separate charges, which he is currently serving.

According to reports, Lester Shum has been sentenced to six months in jail, while Tiffany Yuen and Jannelle Leung will serve four months each.

The gathering to mark the Tiananmen Square crackdown is only allowed in Hong Kong and Macau, however, it was banned this year as authorities cited health concerns owing to the coronavirus pandemic.

Many believe that the vigil, which has been observed since 1990, will never be allowed again in Hong Kong as Beijing has imposed the strict and controversial national security law, which aims at curbing dissents against the government.

In April 1989, protesters gathered in numbers and occupied the Tiananmen Square in Beijing and began the largest political demonstration in mainland China.

On June 3, armed troops opened fire and killed and injured several of those unarmed protesters.

While estimates showed hundreds of people had been killed, authorities denied the reports and discussions related to the act- which is now referred to as the Tiananmen Square Massacre- is prohibited in mainland China.

Hong Kong, however, had been marking the event with a vigil since 1990. But, with Beijing taking control of Hong Kong, it will eventually end the tradition.