Pro-democracy activists on Wednesday demanded the release of Guangzhou-based dissident Lai Rifu, who was arrested two days ago after sharing a video which had made use of the song Glory to Hong Kong, the anthem of anti-extradition bill protesters in Hong Kong.
The video apparently showed sceneries from Guangzhou and had captions which said "This is my homeland, I want her to be free".
In a Facebook post, a group called 'Southern Idiot' said Lai was taken away by a group of about 20 unidentified people when he was walking towards home on Monday with his seven-year-old son. It said his family was contacted by the authorities the next day and told he was in detention for "picking quarrels and provoking trouble".
On Wednesday, around 20 people, including members of the League of Social Democrats, marched to Beijing's liaison office in Hong Kong, chanting slogans in support of Lai.
Civil Party lawmaker Kwok ka-ki, who took part in the rally, said Lai's arrest was unreasonable.
"He didn't say anything to overthrow the communist regime. He just said he would like to support Hong Kong," said Kwok.
"And perhaps he would like to see in future that perhaps mainland China can have the same kind of movement to fight for freedom and democracy."
Lai had also been arrested in 2014 for supporting Hong Kong's Occupy movement.