KUALA LUMPUR, Malaysia (AP) — The search focus for a missing Malaysian jetliner is changing with India saying it is expanding its search to seas west of the Andaman Islands while the international hunt shifted toward the Indian Ocean.

The shift comes amid signs that the jet may have flown on for hours after last contact. It complicates the search by vastly expanding the area the lost jet might be.

It follows remarks by a U.S. official that the Boeing 777 sent signals to a satellite for four hours after the aircraft went missing early Saturday.

Vietnam says it has been asked by Malaysian authorities to consider sending planes and ships to the Strait of Malacca, also to the west of Malaysia.

Meanwhile, China has urged Malaysia's government to release any information it has. Today's appeal by the Foreign Ministry reflects growing frustration among Chinese officials over mixed and conflicting information about the plane, which vanished nearly a week ago with 239 people aboard.