KUALA LUMPUR: An irritated Inspector-General of Police gave reporters a tongue lashing when asked why that only now the police knew of the human mass graves in Perlis-Thailand border.

Tan Sri Khalid Abu Bakar said he was tired of having to answer the same questions and people were "bored" with listening.

Khalid reiterated that police knew of the graves only recently, in May, and the police had no evidence that illegal immigrants had been kept in the jungle camps.

But he further said that "everyone knows about human smuggling and trafficking in that area and that police had not been "sitting idle, doing nothing".

Migrant rights group Tenaganita director Aegile Fernandez was earlier reported saying that family members of the human trafficking victims had told police and the Asean secretariat committee of the trade years ago.

"So I wouldn't say there wasn't any info on the existence of the camps. There was enough info but we were not taken seriously," she had told The Star.

Asked on this Khalid snapped back:

"When did they tell us? When things happen and a discovery is made everyone wants to point fingers to say this person didn't do his duty or didn't take this action," he said.

"I have said this four times. I have said this before. We had no evidence that these migrants had entered the country through these camps. I have said this before," he added.

However, when questioned again, Khalid said police had not been "sitting idle" and human trafficking at the border was well known.

"Everyone knows," he said.

Khalid reiterated that the terrain surrounding the trafficking camps and graves where skeletal remains of scores of victims, believed to be Rohingyas and Bangladeshis, were found were rough and difficult to access.

"Go see yourself. We let 62 reporters go up there and check, you ask them what its like. Because everyday you ask me and I have to explain the same thing. I think people are bored listening. The only person not bored is you," Khalid snapped.

He declined to speak on the two police officers arrested or how many people were being probed in connection to the discovery of the graves.

"I need not tell you (reporters)," he snapped.

Khalid confirmed that the perpetrators of the Wang Kelian graves were among the 37 Malaysians arrested for human trafficking this year.

"We had information that illegal immigrants were being kept against their will but we could not ascertain the location at that time.

"It was until we had information from Thailand and after the first graves were found that we did a check from Tangga Seratus to Kampung Wai.

"From our sweep was where we found the camps and graves," he said, denying a Star report that the graves had been found in January rather than May 11.