HONG KONG: What kind of man would throw acid from a height with intent to harm people he doesn't even know? It's a question many people ask. Even psychologists and criminologists are at a loss to piece together a profile that would assist police in catching the assailant in the latest acid throwing incident.

A bottle of corrosive liquid was thrown from 543 Lockhart Road, Causeway Baby to a pavement teeming with pedestrians at about 10 pm on Saturday. Six were injured, including two seriously.

The attack came one day before the anniversary of the first acid attack, in Mong Kok, on December 13, 2008. A string of similar incidents followed in Mong Kok and Sham Shui Po. The police had offered HK$900,000 and HK$300,00 for leads to catch the culprits, but to no avail.

The attacker is a madman, said Hong Kong University criminologist Borge Bakken.

The attacks were done without demands or messages and simply to inflict suffering, he said.

Noted psychologist Steven Ng Wai-man said there's a high likelihood that the assailant is the same person, given the similarity and timing of the attacks.

"The culprit could be suffering from psychosis or personality disorder. But at the current stage, we have very little information to gain further knowledge," he said.

Chen Zhansheng, assistant professor of University of Hong Kong's psychology department, said the aggression may originate from the assailant's feeling of rejection, ostracism or a sense that he has been treated unfairly.

"But he feels there's nothing he can do to change the reality," Chen added.

The acid attacks give the perpetrator a sense of power and control and also give him the attention he craves, he said.

The fact that no arrests have been made despite efforts in catching the assailant may encourage copycats. But media are playing a crucial role in the deciding the outcome, Chen pointed out.

Copycats copy an act because they see a "reward" for the act. The reward could very well be the mystique generated by media coverage, he said.

Instead, reports on the consequence of the attacks and the suffering of victims would diminish the desire to copy the attacks, Chen said.

Former Royal Hong Kong Police Criminal Intelligence Bureau Commander Steve Vickers is confident that it was only a matter of time before the police bagged their man.

"He may be unstable but he's stable enough to plan these attacks. Since he is deriving satisfaction from his work and clearly craving the attention, it's only a matter of time before he boasts of his work," he said.

Vickers added it was also only a matter of time before the police reward will tempt someone close to the attacker to inform the authority.

(HK Edition 12/15/2009 page1)