KUALA LUMPUR -- No passenger from Chinese mainland aboard the missing MH370 flight was involved in a hijack or terror attack, Chinese ambassador to Malaysia said on Tuesday.

Background check on all passengers from Chinese mainland has found no evidence on their involvement, Huang Huikang said.

The Malaysia Airlines flight went missing in the early hours of March 8 en route from Kuala Lumpur to Beijing. There were 239 people on board, including 154 Chinese.

A multinational search has so far failed to determine its whereabouts, and what happened to the plane remains a mystery.

Huang said China has started search in its own territory along the northern corridor, while nine naval vessels are prepared to scour new areas along the southern corridor after concluding their futile hunt in South China Sea.

Based on latest information, the new search areas encompass a northern corridor stretching approximately from the border of Kazakhstan and Turkmenistan to northern Thailand, as well as a southern one from Indonesia to the southern Indian Ocean.

The Chinese envoy said since a criminal investigation has been launched into the missing plane, some information is not suitable for disclosure at this moment, without giving further details.

"The probe into the incident's cause is not suitable to be conducted in a high-profile way," he said.

Huang said China has been in close contact with Malaysia since the very beginning and well informed of latest developments.

"The Malaysian government has been doing its best in search and investigation, but it lacks experience and capability to handle this kind of incident," he said.

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