KUALA LUMPUR, Malaysia–Senior Malaysian officials are growing increasingly frustrated and privately incensed at what they see as excessive pressure from China to find the missing Flight 370.

The search for the jet, which vanished in early March, is testing ties between the two countries in a year that their governments had earlier declared “China-Malaysia Friendship Year” to mark 40 years of diplomatic relations.

Two-thirds of the 227 passengers aboard the flight were Chinese, and some of their family members have led a wave of criticism of Malaysia–with the Chinese government’s tacit support–putting Kuala Lumpur on the defensive.

Many of the passengers’ relatives do not believe the official account that the plane was lost at sea and accuse Malaysia of hiding what really happened. Some of the Chinese residents have taken part in protests in that would have been impossible if directed at their own government, including marching in the streets of Beijing carrying signs with slogans such as: ” Malaysia Airlines, You Owe Us Answers!”

… Ei Sun Oh, a Malaysian and senior fellow with the S. Rajaratnam School of International Studies at the Nanyang Technological University in Singapore, said that if the majority of passengers had been U.S. citizens, Americans “would voice dissatisfaction, but they would go to court and sue Malaysia left and right.” Beijing appears to be eager to distract attention from its own limited capacity to find the airplane by allowing protests to take place, he said. “What the Chinese government fears the most is its own population turning its anger against them.”