With a burly figure and bald head, it is not easy for Mr Lau Chak Kei to blend in with a crowd.

“When I’m off duty and go out now, my wife would ask me to wear a hat and sunglasses. That’s her way to protect me,” the veteran Hong Kong police officer beamed at his own words. “But I don’t think the disguise works.”

For the past over 20 years, protecting others in danger has been Mr Lau’s unwavering faith.

Therefore, when the news came on the night of July 30 that a man was beaten unconscious by a mob because of his political views, Mr Lau and his team immediately rushed to the site, knowing that they themselves would become the target amid the intensity of anti-police sentiment.

What happened in the next hour was overwhelming even for a veteran law enforcement officer like Mr Lau.

“There were over 1,000 protesters outside the police station, and when they saw us coming, they surrounded us and attacked us with bricks and sticks,” he recalled.

Besieged by the mob and separated from the rest of the team, Mr Lau and another colleague were shoved around and lost their balance. Then, someone took off Mr Lau’s helmet by force.

In the following seconds, fists landed on his head, and Mr Lau started to feel dizzy.

Stuck in the chaos, Mr Lau could feel some hands attempting to grab his shotgun loaded with beanbag rounds.

“The moment I realised that those people were trying to take away the gun, all the dizziness disappeared,” said Mr Lau.

After securing his shotgun with the strength left, Mr Lau pointed it at the mobs for warning. He did not fire a single shot that night.

However, that moment was captured by waiting cameras. Without providing the context, some media and protesters immediately portrayed Mr Lau as the poster child for police brutality in the months-long unrest.

Within an hour, personal data of Mr Lau and his family were disclosed online and he was bombarded with hundreds of threatening phone calls, among which some threatened to “kill the whole family” of his.

At online forums such as LIHKG, radical protesters spread rumours and distorted information about police, or simply vent their unrestrained anger. Mr Lau is still a regular target.

After an off-duty Hong Kong police officer was stabbed by a trio of masked men in late August, Mr Lau and his family had to take the threats seriously.

“I felt nauseated at the ambush against that police officer and my wife broke down in tears,” Mr Lau said. “How can you hurt someone who are strangers to you simply because they are policemen.”

As the unrest in Hong Kong entered the third month, prolonged and escalating violence by radical protesters has taken a heavy toll on Hong Kong’s law enforcement. According to the Hong Kong Police Force, at least 200 personnel have been attacked and injured during the continued unrest.

Amid the rising tensions between rioters and the police force, well-known for its discipline and professional performance to maintain social order, families of the police have also become a target of the black-clad men.

So far, the personal data of more than 1,800 police personnel and their families have been illegally disclosed online since June, including pictures of the children of the police and information about their schools and classes. In some cases, teachers reportedly encouraged bullying against children of the police.

“Before the new semester started, my kids’ teachers called me to reassure my wife and I that our kids will be taken good care of,” Mr Lau said. “To us parents, it was such a great relief to know that rationality still prevails in our schools, that most of the teachers are there protecting our kids.”

One and a half months after that eventful night, Mr Lau still suffered fractured bones in the knee and double vision after protesters aimed laser pointers at his right eye.

He said he was healing from the injuries and the Hong Kong society needs healing from the trauma too.

Despite the continued unrest, Mr Lau said these days he often run into ordinary Hong Kong residents who recognised him in the street and approached him with words of thanks.

They told him that they could not support the police publicly over concerns about their own personal details being exposed and put online. Mr Lau said he understood their concerns.

“It means so much to us that Hong Kong people still count on us, and we count on their support,” Mr Lau said.

“It is okay if you have to be silent for now, but, please, keep on supporting us,” he said.