A former engineer was on Thursday jailed for five years after he admitted to stabbing a police officer during a riot in Causeway Bay two years ago.

District Court judge Frankie Yiu said Wong Kwan-wa was among 300 people who took part in a protest, which turned into a 10-minute riot, on July 1, 2020, less than 24 hours after the national security law took effect in Hong Kong.

The court heard that Wong, 26, stabbed the officer in the left arm with a folding knife outside Sogo department store when the policeman was trying to subdue Law Kok-sum, another defendant in the case.

Hours after the assault, Wong boarded a plane bound for the United Kingdom, but was arrested by the police before it took off.

He had earlier pleaded guilty to taking part in a riot and wounding the officer with intent.

In mitigation, Wong’s lawyer said he was born to a poor family and had worked hard to achieve what he had. The lawyer said Wong was kind and loving, and was not a leader in the protest, but made a big mistake out of recklessness.

Sentencing Wong, the judge noted the injury could have cost the officer his life, adding that his career development had also been affected because he had since been deployed to handle administrative work.

The judge said the case was of a serious nature, but said he had taken into account Wong’s guilty plea and his clear criminal record.

Sentencing for Law, 20, was adjourned to October 31 pending a training centre report.

Another co-defendant in the case, Percy Chau, 21, was earlier sentenced to 33 months in jail for rioting and obstructing an officer on duty.