AP
The home of Fariq Abdul Hamid, the first officer of Malaysia Flight 370.
On Saturday, police officers were seen entering the home of pilot Zaharie Ahmad Shah, which was reportedly searched, according to The New York Times. The co-pilot's home was also visited, according to CNN.
As a number of commercial pilots told NPR's "All Things Considered" on Friday, with the exception of the transponder, which can be shut off at the flick of a switch, other onboard tracking systems are not as easy to disable - leading investigators to believe whoever turned off tracking systems had intimate knowledge of them.
The captain and first officer of the plane were both experienced pilots. Capt. Shah, 53, began with the airline in 1981 and had logged 18,365 flying hours, while First Officer Fariq Ab. Hamid, 27, joined in 2007 and had 2,763 hours logged.
The Times has more:
The authorities may also be looking at an aviation engineer who was among the passengers. The New Straits Times, a newspaper published in Malaysia, interviewed a man who said that his son, an aircraft engineer, had been on the flight en route to China to work on Malaysia Airlines planes. The son, Mohd Khairul Amri Selamat, was identified on the passenger manifest as a 29-year-old Malaysian. A company spokeswoman said early Sunday that the passenger was an employee of a private-jet firm, not Malaysia Airlines.
Over the past two days, the focus of the investigation has morphed from a belief the plane may have suffered a catastrophic failure to the possibility it had been hijacked by passengers or members of the crew. The reasoning, officials noted, came down to the shut down of onboard tracking systems and deliberate redirection of the plane away from its Beijing-bound flight path.
"An aircraft which was believed but not confirmed to be MH370 did indeed turn back," Malaysian Prime Minister Najib Razak said in a press conference on Friday. "It then flew in a westerly direction back over Peninsular Malaysia before turning northwest. Up until the point at which it left military primary radar coverage, these movements are consistent with deliberate action by someone on the plane."
The move to investigate the flight crew more thoroughly does not mean they have been declared suspects, The Times notes. But it does at least give officials something more solid to look into at a time when the search-and-rescue has turned up few signs of the aircraft's location.
That search greatly expanded Friday, as the Malaysian P.M. introduced two massive new search "corridors" - northern corridor stretching from northern Thailand to the border of Kazakhstan and Turkmenistan, and a southern corridor stretching from Indonesia to the southern Indian Ocean.
"Clearly the search for MH370 has entered a new phase," Razak said Friday. "We hope this new information brings us one step closer to finding the plane."