BEIJING, March 19 -- So far, no trace of missing flight MH370 entering Chinese territory or airspace has been found, a Foreign Ministry spokesman said here Wednesday.

"With a vast area of territory, search work is still in full swing," spokesman Hong Lei told a daily press briefing. Radar and satellite data for parts of China covered by the "northern corridor" have been examined in meticulous detail at the request of the Malaysian side.

Official Malaysian sources say the plane could be anywhere along a giant arc extending from Kazakhstan in the north to the Indian Ocean in the south.

Chinese naval ships on Wednesday left their rally point near Singapore and split into two groups, one heading north and the other south on the second phase of the search.

Hong said the areas cover seas to the west of the Bay of Bengal and Indonesia, a total of 300,000 square kilometers.

"China has shared satellite data with Malaysia at the request of the Malaysian side," Hong said, adding that China will give further information when data is completely verified.

"China has conveyed Malaysia's request to all countries related through diplomatic channels to express hope for their efforts to take part in the international search," Hong said, calling on further coordination with Malaysia in the search.

"China has repeatedly asked the Malaysian side to take care of relatives of passengers and respond to their reasonable concerns," Hong said.

Malaysia Airlines flight MH 370, a Boeing 777-200 aircraft, carrying 227 passengers and 12 crew en route from Kuala Lumpur to Beijing, mysteriously disappeared from radar in the early hours of March 8.