U.S. President Barack Obama is calling the search for the missing Malaysian airliner a "top priority" for the United States.
Mr. Obama told Dallas television station KDFW Wednesday that he has put every available resource into the search. The president said he can only imagine what the families of the missing passengers are going through.
Frustration by families of some Chinese passengers boiled over Wednesday as they screamed demands at Malaysian officials at a briefing, accusing them of lying, giving conflicting information and behaving like gangsters.
Malaysian police forcibly removed grieving and wailing relatives from the room.
Malaysian Defense Minister Hishammuddin Hussein said he understands emotions are high, adding that authorities are trying their very best to find the plane.
Most of the 239 people on board the Boeing 777 were Chinese.
Flight 370 disappeared March 8 while traveling from Kuala Lumpur to Beijing.
Hussein said investigators are trying to narrow the search area, which now covers more than seven million square kilometers, from Kazakhstan to the southern Indian Ocean.
Investigators believe the plane was deliberately diverted, either south toward the Indian Ocean or north toward Central Asia.
Malaysian police found a flight simulator in the Kuala Lumpur home of the pilot, Zaharie Ahmad Shah. Hishammuddin says experts are trying to retrieve data that was deleted from the device. He says there is no evidence implicating Zaharie in any wrongdoing.
There is also no evidence of criminal activity by the co-pilot or any of the passengers.
U.S. Attorney General Eric Holder says the FBI is working with Malaysia, but that U.S. authorities have no theories on what happened to the jet.
( Unidentified relative of Chinese passenger [in Mandarin] )
"Every day I'm confronted by your boring questions. I'm facing you everyday, I'm fed up with it. I know you know we can do nothing but vent our anger and cry, we can do nothing to you. Aside from lying, deceiving, you have been playing the gangster."
Scott Hamilton of the U.S.-based aviation consulting firm Leeham Company tells VOA the Malaysian government appears to be "completely over their heads" with the investigation.
"They've probably never had anything even remotely like this to deal with. (They) didn't know what to do with it, didn't know how to deal with the pressure from the Chinese government, which of course was very immense given the number of Chinese on the airplane. You had one agency of the government saying one thing, you've had another agency saying something contradictory. I just think they've been totally over their heads on this."