A masked assailant hit a man over the head with a drain cover in Hong Kong at 1am on Sunday, Dec. 1, 2019.

Police said a 53-year-old man suffered serious head injuries from the attack.

The man who was attacked had been clearing protesters’ roadblocks.

The assault has sparked a manhunt.

The incident occurred at the junction of Nathan Road and Mong Kok Road in Mong Kok.

The attack was caught on video (Graphic content warning):

South China Morning Post reported that a police spokesman said they “seriously condemned the violent behaviour of the rioter” and have attached “great importance” to the case.

The police said the man could have been killed from the impact of the blow.

“Police absolutely do not tolerate anyone who uses violence to achieve their aims,” the spokesman said.

“We will take law enforcement action resolutely to restore order in society and bring all lawbreakers to justice.”

The case has been classified as assault and theft by police as the victim’s mobile phone was stolen.

As of Sunday afternoon, no arrest was made.

The victim was taken to hospital and discharged later in the day.

What happened

A video capturing the incident showed the victim removing barricades on his own.

Several masked protesters approached and shouted at him.

He took out his mobile phone to record the scene.

A man wearing a mask appeared from the side and hit the man with a elongated object.

The victim fell and remained motionless.

He was conscious after the attack, the video showed, but was bleeding from his head.

He was attended to by a first aid volunteer.

On Saturday night, large groups of protesters gathered in Mong Kok and Prince Edward in Kowloon.

Police fired tear gas in Mong Kok at those who were blocking roads and had set fire to an entrance of Mong Kok railway station.

Those on the streets appeared at the same location exactly three months after riot police violently dispersed people inside Prince Edward MTR station and on a train.