One person was flying on an Italian stolen passport...so you definitely cant rule out criminal act.
http://news.yahoo.com/malaysia-airlines-plane-missing-stolen-passports-raise-suspicions-164600315.html;_ylt=AwrTccgjVxtTIUgAuJAPxQt.;_ylu=X3oDMTBsOXB2YTRjBHNlYwNzYwRjb2xvA2dxMQR2dGlkAw--