Search teams are scouring waters off both sides of the Malaysian peninsula, amid confusion over a missing Malaysia Airlines plane's last known location.
Malaysia's air force chief has denied reports that the plane was tracked to the Malacca Strait in the west.
Vietnam has despatched a plane to investigate an eyewitness report of a possible object burning in the sky east of Vietnam. Flight MH370 went missing on Saturday. It had 239 people on board. Authorities have been searching for the plane, which disappeared en route from Kuala Lumpur to Beijing, for the past five days. Earlier this week, Malaysia widened the search for the missing plane amid conflicting reports on its last known position.