A total of 39,046 Indian nationals are believed to be staying illegally in Malaysia as of June 2009, after entering the country on tourist visas, official news reports said Wednesday. Malaysian Prime Minister Najib Razak said the "missing" people were mostly from Chennai, adding that authorities viewed the problem as worrying as these immigrants could not be monitored.

"We just don't know where these people are now, ... probably still in Malaysia for economic reasons," Najib was quoted as saying by the official Bernama news agency.

"We would like the Indian people to visit Malaysia as tourists. We have been quite liberal. We want genuine (tourists). They are most welcome."

He said he would bring up the issue with his Indian counterpart during a three-day visit to New Delhi beginning Jan 19. Malaysia is home to thousands of illegal workers, mostly from neighbouring Indonesia, the Philippines and India.