Seven people were injured after an unknown group attacked them by shooting them fireworks from a moving car outside a police station in Tin Shui Wai in the New Territories in the early hours of Wednesday.
Over 100 people gathered outside Tin Shui Wai Police Station after three young people were reportedly taken there by police.
The young people. aged around 16 to 17, were reportedly trying to guard the Lennon Wall near Tin Sau Road Pak while a middle-aged man took a photo of them and damaged memos stuck on the wall.
It was understood that the middle-aged man called the police and claimed that the three teenagers attacked him.
Police arrived carrying shields but passersby surrounded the accused and said they had not been handled fairly. More officers were called in to assist and they took the three young people back to the police station.
A few hundred people gathered outside the police station and called for the three to be released. They were eventually given bail at around 2am.
At 2.30am, when there were still a few hundred people outside the police station, a black private car drove past the police station and people inside lobbed fireworks into their midst before speeding off up Tin Yiu Road.

Seven people were injured and five of them were taken to hospital. Meanwhile, the driver of a Kowloon Motor Bus swerved out of its way when the fireworks lobbed and crashed into railings. Two people were injured.
The police bomb disposal unit was also called to the scene and the protesters gradually left at 4am.
On Tuesday night, protesters also surrounded the Kwai Chung police station in support of 44 colleagues who were charged with rioting earlier in the day.
Riot police were deployed to disperse the crowd and used pepper spray on a number of occasions. One officer was seen pointing a Remington shotgun at the crowd outside the Kwai Chung MTR Station, where there were both residents and protesters.
Protesters reportedly threw water bottles and umbrellas at the officer and his colleagues when they dispersed the crowd.
As of noon on Wednesday, the first batch of 24 defendants, aged from 18 to 40, were released on cash bail of HK$1,000 (US$127). The Eastern Magistrates Courts imposed a midnight curfew on some of them, Radio Television Hong Kong reported.
Most of the defendants are students, but others included a pilot, a teacher and an office clerk. More than 1,000 supporters stood outside the court, chanting slogans to support the defendants while a typhoon approached the city.

People convicted of rioting in Hong Kong can face a jail term of up to 10 years.
Jailed pro-democracy activist Edward Leung Tin-kei wrote a letter to protesters opposed to the extradition bill, calling on them not to yield to hatred.
Last year, Leung was sentenced to six years in jail in connection with rioting during the Mong Kong unrest in 2016, dubbed the ‘Fishball Revolution’.
In an open letter addressed to “Hong Kong People” dated July 26 and posted on his Facebook on Monday, Leung hoped the protesters would not become overwhelmed by hatred. He urged them to remain vigilant and thoughtful at times of difficulty.
Leung said he had been separated from society by spending more than a year and a half in jail, and could not imagine the suffering and pain the protesters had been suffering both mentally and physically.
“As the number of arrests and injuries rise, I think of the future you will face, and those wounds that are hard to heal. I want to know who can mend this wound in society.”
But he hoped protesters would understand that because of their love of Hong Kong, they had showed unrivalled courage, and had changed Hong Kong’s history. He said it was understandable that many of them would feel angry as long as justice was not served, but called on them not to be overwhelmed by hatred.
Leung hoped the protesters to maintain a clear mind, especially in difficult times.

“I always remind myself that politics is not only about making sure our supporters continue to support us, but to change the mind of those who don’t support us, to agree with our direction,” he said.
“What we need is not to gamble our precious lives, but to grow perseverance and hope from suffering,” he said.