Malaysian activists condemned police on Saturday for using marker pens to “brand” 30 suspected prostitutes with large crosses on their foreheads.

Newspaper pictures published on Friday of the 29 Chinese and one Vietnamese arrested in a vice raid on a high-end nightclub on the holiday island of Penang sparked outrage among rights groups who demanded an investigation.

“It is absolutely wrong and it’s illegal because it amounts to taking away of the dignity of the suspects and there is nothing in the law that allows for such marking of suspects,” N. Surendren, of rights group Lawyers for Liberty, told AFP.

“In fact, such markings can be considered a form of assault so police must initiate a criminal investigation to determine who was responsible for this assault on the women,” he added.

State police chief Ayub Yaakob defended his officers’ actions, saying they were left with no choice given the “chaotic situation”, the New Straits Times newspaper reported.

“Some of them (the women) even ran into shops and tried to buy new clothes to blend in with female members of the public. Because of this we were forced to mark X’s on their bodies,” he told the paper.

However, rights group EMPOWER said police had “publicly humiliated” the women by marking them with crosses.

“The duty of the police was to arrest and investigate, not publicly humiliate these women. And why have you not done the same thing to the pimps and the customers that were also arrested,” executive director Maria Chin Abdullah said.

Aegile Fernandez, coordinator of rights group Tenaganita, said the incident showed that Malaysian police had a long way to go in respecting the rights of the accused.

“If they disregard the women’s rights and mark their bodies in public, then what do they do in private?” he asked.

A UN team investigating claims of abuse and torture in Malaysia last year found a main police detention centre holding illegal immigrants in overcrowded conditions with poor sanitation and inadequate medical facilities.

By Agence France-Presse, Updated: 6/4/2011