Early in the morning, just hours after Malaysian Prime Minister Najib Razak said the plane had crashed in the Indian Ocean, an unidentified family member read out a statement at the Beijing hotel where many of the relatives of those on board were staying, denouncing the airline, the Malaysian government and military for "constantly trying to delay, hide and cover up the truth".
It was "an attempt to deceive the families of the passengers and an attempt to deceive the people of the world", said the statement, which was later posted on a Chinese microblog by the "Malaysia Airlines MH370 Family Committee".
In a later statement, the families said they would head to the Malaysian Embassy in Beijing on Tuesday morning to "protest, seek the truth and the return of their family members."
The families, in a statement, said they would "take all possible means" to pursue the "unforgivable guilt" of the airline, the Malaysian government and the military.
"These despicable acts have not only fooled and devastated physically and mentally the families of our 154 Chinese passengers, at the same time they have also misled and delayed the rescue operation, wasted a lot of manpower, material resources and lost the most precious time for the rescue efforts," the unidentified family member told reporters.
"If our 154 loved ones on board have lost their precious lives on the plane because of this, then Malaysia Airlines, the Malaysia government and the Malaysia military are the real executioners who have killed our loved ones."
Bad weather and rough seas on Tuesday forced the suspension of the search for any wreckage of the missing Malaysian jetliner that officials are now sure crashed in the remote Indian Ocean off Australia with the loss of all 239 people on board.
On Monday night, there were hysterical scenes at the hotel, with some of the relatives wailing and being carried out on stretchers.
Malaysia Airlines has promised to take the relatives to Australia, the focal point of the search.
Australian Defence Minister David Johnston said Prime Minister Tony Abbott wanted to help the families, the majority of whom are from China.
"I know the prime minister is very, very concerned that we extend every possible courtesy," Johnston told Fairfax radio.
"They have had an emotional rollercoaster for two weeks, my heart goes out to them. We will do everything we can to give them some semblance of closure, in what we now know is a very serious disaster."