Wong Kin-keung pleaded guilty to throwing corrosive liquid at Shum Chi-shing with intent to cause him grievous bodily harm. The high court heard he splashed sulfuric acid of 73 percent concentration on Shum on November 21, 2020.

Shum, 63, suffered third-degree burns on 18 percent of his skin area, with the worst being on the right side of his face, chest, right arm and legs.

Wong had assaulted Shum with a hammer in mid-2020, for which he was given one-month jail suspended for 12 months. However, one day later, he splashed acid on Shum.

In passing sentence yesterday Justice Audrey Campbell-Moffat slammed Wong, saying she could not understand how his hatred could evolve into such an attack.

She said Wong posed a clear risk to the public because he could not control his temper, and dismissed a defense's explanation that Wong was using the acid to sanitize his "urinal" bottle at the time.

Wong didn't show regret as well, she said, as he laughed and watched Shum suffer without offering help.

She set Wong's sentence at 18 years in jail and reduced it to 12 years on account of his guilty please, but added another month due to his violation of his previous sentence.

Shum was unhappy with Wong who always placed his wheelchair in the corridor.

Shum had filed complaints with the management several times before the two attacks.

The court also heard police seized three bottles of corrosive liquid and a urinal bottle at Wong's home, which Wong had poured the liquid into before splashing Sham.

In mitigation, the defense said Wong was divorced, and his livelihood depended on social security assistance.

The lawyer also said Wong started using a wheelchair in 2018 after a failed spine surgery, and hoped the court would be lenient given his health condition.