In Malaysia, itīs a police investigation as well. Quoting Reutersī article from today, mentionig the police may search the pilotīs home:
Malaysian Transport Minister Hishammuddin Hussein said he could not confirm the last heading of the plane or if investigators were focusing on sabotage.
"A normal investigation becomes narrower with time... as new information focuses the search, but this is not a normal investigation," he told a news conference. "In this case, the information has forced us to look further and further afield."
Investigators were still looking at "four or five" possibilities, including a diversion that was intentional or under duress, or an explosion, he said. Police would search the pilot's home if necessary and were still investigating all 239 passengers and crew on the plane, he added.
MH 370 Investigators Focus On Foul Play - Reports