Malaysia's acting Transport Minister Hishammuddin Tun Hussein speaks during a news conference about the missing Malaysia Airlines flight MH370, at Kuala Lumpur International Airport March 13, 2014.

An unspecified Malaysian official was quoted as saying Saturday that investigators have concluded that missing Malaysia Airlines Flight MH370 was hijacked.

According to the report, which is yet to be corroborated, the hijackers have rich flying experience and they switched off communication devices deliberately and steered the Boeing 777 aircraft off course.

Although piracy is no longer a theory, the motives are yet to be established, the official was quoted as saying.

Malaysian Prime Minister Najib Razak is scheduled to hold a press conference in Kuala Lumpur in the early afternoon.

A multinational intensive search has so far failed to locate the plane, which disappeared from radar early Saturday morning last week while carrying 239 people from Kuala Lumpur to Beijing. Among the 227 passengers 154 are Chinese.