A man from the Chinese mainland was beaten up by a crowd of rioters and radical protesters at the Hong Kong airport on Tuesday night, and the protesters claimed the reason for the attack was because they believed he was a "mainland policeman pretending to be a protester."

Observers and mainland netizens were angered by what they called the ruthless and crazy behavior and criticized the airport for failing to manage the situation and ensure the safety of passengers in the terminal building.

Videos and pictures circulating online showed that rioters kicked and punched the young male traveler. The victim was handcuffed and dragged through the airport by the rioters with a sign on his back that read "I am a mainland police officer. I am here to sabotage the protest."

The Global Times has learned that at around 7pm Tuesday, a large group of protesters surrounded the traveler and searched his wallet for ID. After searching his name online, they found that his name happens to be the same as an auxiliary police officer in Shenzhen.

Without confirming his identity or the purpose of his travel to Hong Kong, the rioters began assaulting him by cuffing his hands behind his back, splashing water on his head and pointing laser beams into his face. He was denied medical help for hours until being rescued at around 10:40pm by Hong Kong police.

According to police, a passenger at Hong Kong airport was set upon by "protesters" and needed medical treatment, but the protesters did not allow ambulancemen to take him to hospital.

Hong Kong police received a request for assistance from the airport and when they arrived, they instructed the protesters not to prevent the injured passenger from getting medical treatment.

The police stressed that this was not a site-clearing operation, and the mission was to allow the passenger to be taken to hospital.

"Everyone has the right to personal liberty and personal security, which are the most basic human rights. Rioters who encircled and attacked the passenger in the Hong Kong International Airport, violated human rights and the rule of law, no matter who the passenger actually was," Albert Wu, a practicing barrister in Hong Kong, told the Global Times.

These violent protesters and rioters should be arrested and prosecuted as soon as possible, so as to safeguard law and discipline and protect the basic human rights of people in Hong Kong, Wu said. "As long as they are people, they cannot be treated like that."

"Rioters in Hong Kong are targeting mainland tourists and passengers as a way of venting their frustrations. They were mad and crazy and were carried away by violence. No matter what their motivations were, the act of violence is unacceptable," Li Xiaobing, expert on Hong Kong, Macao and Taiwan, from Nankai University in Tianjin, told the Global Times on Tuesday night.

Observers and mainland netizens are angry and criticized the airport's administration for doing nothing to stop the violence. "Is the airport supporting the violence against mainland passengers as well?" said a netizen on Sina Weibo.

Zhi Zhenfeng, a legal expert at the Chinese Academy of Social Sciences, told the Global Times on Tuesday that Hong Kong airport has failed to implement effective measures to cope with the rioters and showed little will to do so. He said the airport could have shut off the air conditioning, water supply or cut off the power, but in the end chose not to respond to violent acts.

"Isn't this indirect support of the rioters?" Zhi noted.

He urged Hongkongers who wish to maintain the rule of law to make their voices heard or otherwise they will be held historically accountable for the fall of the city.