(NEW YORK) -- The investigation into missing Malaysia Airlines flight MH370 has included a probe of the plane's two pilots, but Malaysian authorities said Friday they have yet to search their homes. Focus on the pilots has intensified following indications that two of the plane's communication systems were shut down in what U.S. officials believe was done manually, not by a catastrophic event.
When asked at a news conference Friday if investigators were looking at whether the pilots could have involved in whatever happened to the plane, Malaysia's Transport Minister Hishammuddin Hussein replied, “We are looking at that possibility.”
“The investigation into the pilots is ongoing,” he said in response to another question, but said they have not yet searched their homes.
The last words from the plane came when Malaysian air traffic control told the plane that it was handing over control to the Vietnamese. One of the pilots responded, "All right, good night." Their response gave no indication of any problems with the flight.
When asked why their homes had yet to be searched Hishammuddin said only, "That is in the realm of the police."
Both pilots are Malaysian men whose behavior had no obvious red flags.
The plane was piloted by Capt. Zaharie Ahmad Shah, 53, a married father of three grown children with more than 18,000 hours of experience in the air. He has been described as an affluent aviation buff, with a home in a gated community.
Shah's online presence makes clear his passion for flying. He posted videos of himself in front of a home flight simulator system he had set up. In some of the videos he talked about flying. In others he instructed viewers how to do home fixes that save money.
Shah's YouTube account also shows an interest in videos dealing with atheism, frustration at Malaysian politics, and an appreciation of American comedians including Louis C.K. and Sarah Silverman.
Police have been stationed outside of his home since the plane disappeared a week ago, but have not searched his home, according to Malaysian authorities.
The co-pilot or first officer on the flight was Fariq Abdul Hamid, 27, who has been flying with Malaysia Airlines since 2007 and has logged more than 2,000 miles in the air.
Earlier Friday, ABC News visited the mosque where Hamid prays on Fridays when he is not flying. Imam Ahmad Sharafi Ali Asrah characterized Hamid as a good man. The mosque Friday prayed for him and his family.
Hamid lived two doors down from the mosque, where his parents also attended services.
In the days following the plane's disappearance, a South African woman named Jonti Roos told Australia news Channel Nine that she and her friend were invited into the cockpit by Hamid on a flight in 2011, and were allowed to stay in the cockpit for the flight's duration. She produced photos of them together.
Malaysia Airlines said it was shocked by the photos but has not been able to confirm Roos' story.
The two pilots would have been in the cockpit behind a reinforced door during the flight. They could have opened the door to use the restroom or communicate with flight crew, but otherwise it would have remained a barrier between them and the passengers.
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