Families of Chinese passengers on board missing Malaysia Airlines Flight MH370 protested outside the airline’s office demanding that authorities overturn a declaration that categorized all passengers on board as presumed dead. The Boeing 777 went missing on March 8 with 239 people, mostly Chinese nationals, on board during a flight from Kuala Lumpur to Beijing, and is yet to be found.

Fifteen relatives of the plane's Chinese passengers protested Thursday, wearing white caps and red T-shirts bearing the words, "Pray for MH370," local media reports said. They also reportedly carried placards that read, "Who can tell us what happened", "Come back MH370" and "Today it is us, Tomorrow it could be you." Malaysia Airlines later released a statement saying that the airline’s CEO Ahmad Jauhari Yahya and members of the management committee met with three of the passengers' next-of kin who handed a letter to the authorities. The airline said that it would respond to the letter in the next few days.

“Whilst the airline continues to regularly communicate with the families via its Family Communications and Support Centre (FCSC) in Beijing, it is in no position to provide any further clarification or technical information on the fate of MH370 other than what is already available in the public domain,” the statement read.

According to reports, more Chinese families are expected to arrive in Malaysia this week. The plane was carrying 152 Chinese citizens.

Investigators believe that the plane crashed in a remote part of the southern Indian Ocean and a massive search operation, which has now become the costliest in aviation history, is still ongoing. The search is currently concentrated along the seventh arc, which has been described as “a thin but long line that includes all the possible points where the last known communication between the aircraft and the communication satellite could have taken place.”

Last month, Malaysia declared the disappearance of Flight MH370 “an accident,” and stated that everyone on board was now presumed dead. Authorities said that the declaration was made to clear compensation claims for the passengers' next-of-kin, and that the search for the plane "remains a priority."

"At this juncture, there is no evidence to substantiate any speculations as to the cause of the accident," Malaysia's civil aviation chief Azharuddin Abdul Rahman had said at the time.

Meanwhile, in the update on the search Wednesday, the Joint Agency Coordination Centre gave details about the equipment used in the search for the aircraft. The agency said that the search is being carried out using different types of subsea vehicles, which are equipped with towed vehicles to scan the ocean floor and an unmanned underwater vehicle.