Here are three quotes from an interview of the Malaysian Transportation Minister (the guy who took the lead at the most recently televised press conference) by a CCTV America interviewer:
"Whether it is a hijacking, whether it is intentional, whether it’s under duress, whether it is
some psychological reasons, who did it."
"But the Prime Minister indicated today that because of circumstances and corroborated facts, we are now intensifying our investigation on the
personalities involved and that is clearly been indicated to our police especially.'
"I want to assure the families especially, we will not give up. We will continue to look for that plane. That is our sole, main focus at the moment. Because notwithstanding whether it is terrorism, whether it’s hijacking,
whether it’s psychological, whatever the issues are out there, my main focus as the minister in charge is to find the plane."
http://www.thestar.com.my/News/Nation/2014/03/16/Missing-MH370-full-hisham-cctv-transcript/
I think they are actively investigating if the Pilot
"ran amok" in an airline pilot style.
From Wikipedia:
"Running amok, sometimes referred to as simply amok,[1] also spelled amuk, from the Malay,[2] is "an episode of sudden mass assault against people or objects usually by a single individual following a period of brooding that has traditionally been regarded as occurring especially in Indonesian culture but is now increasingly viewed as psychopathological behavior occurring worldwide in numerous countries and cultures."
"Although commonly used in a colloquial and less-violent sense, the phrase is particularly associated with a specific sociopathic culture-bound syndrome in Malaysian culture."
"A widely accepted explanation links amok with male honor (amok by women is virtually unknown).[12] Running amok would thus be both a way of escaping the world (since perpetrators were normally killed) and re-establishing one's reputation as a man to be feared and respected. Some observers[who?] have related this explanation to Islam's ban on suicide, which, it is suggested, drove Indonesian men to create circumstances in which others would kill them."
[ame="http://en.wikipedia.org/wiki/Running_amok"]Running amok - Wikipedia, the free encyclopedia[/ame]