Twelve Chinese families with relatives aboard Malaysia Airlines Flight 370 have filed a lawsuit in a Beijing court, one day before the deadline for pursuing litigation against the carrier.

The plane disappeared on March 8, 2014, with 239 people — including 153 Chinese citizens — on board en route from Kuala Lumpur to Beijing. Under international agreements, families have a two-year window to sue following an air accident.

The group's lawyer, Beijing-based attorney Zhang Qihuai, said the ultimate goal of the lawsuit is "to find out the cause of the accident and those who are responsible."

The lawsuit, lodged in a transportation court, also named Boeing and jet engine manufacturer Rolls-Royce among the defendants. The court will decide if and where to hear the case.