No evidence has been found linking the 153 Chinese passengers aboard the missing Malaysia Airlines flight to terror or hijacking, state media said Tuesday, citing Beijing's envoy in Kuala Lumpur.

China's ambassador to Malaysia Huang Huikang also said China had begun searching for the aircraft on its own territory amid a huge international search operation covering vast areas north and south of the plane's last-known position.

Huang said background checks on all passengers from the Chinese mainland on board missing flight MH370 did not find any evidence that they were linked to a hijacking or terrorist attack on the jet, the official Xinhua news agency reported.

After taking off from Kuala Lumpur heading to Beijing, the jet disappeared on March 8 with 239 people on board.

Twenty-six countries are now helping to hunt for the plane after satellite and military radar data projected two huge corridors through which the plane might have flown.

The northern route stretches in an arc over south and central Asia, passing across far western China while the southern corridor swoops deep into the southern Indian Ocean west of Australia.

The investigation has zeroed in on the plane's captain, Zaharie Ahmad Shah, and his co-pilot Fariq Abdul Hamid, with a key question being who was in control of the aircraft when it veered off course about an hour into its flight.