Malaysian Inspector General of Police Khalid Abu Bakar said Wednesday that the search for missing Malaysia Airlines flight MH370 was a criminal investigation, and there were things they could not share, according to local newspaper New Straits Times.

"We are investigating based on the four areas of focus ( personal and psychological problems, sabotage and hijacking)," Khalid said at a press conference after opening the Royal Malaysian Police Quality and Innovation Seminar 2014.

He said until now there had been about 170 statements recorded from family members of the passengers and crew on board the missing jetliner.

Khalid said the investigators did have some clues of what happened, but they would not reveal anything as the investigation was ongoing.