The investigators are not ruling out suicide by the captain or co-pilot as a probable cause for the disappearance of Malaysia Airlines flight MH370. According to Huffington Post, the co-pilot of the missing Malaysian Boeing 777 spoke the last words.

On March 8, Malaysia Airlines flight MH370 vanished with 239 people aboard. Investigators are convinced that the plane was diverted thousands of miles off course by an expert in commercial navigation.

Ahmad Jauhari Yahya, airline chief executive said that they don't know when one of the airplane's automatic tracking systems had been disabled. On Sunday, the suspicions of hijacking had intensified when officials revealed that the last message from flight MH370 was "all right, good night." After this the automatic tracking system - "ACARS" was disabled.

Experts believe that the airliner's transponder can be disabled by flicking a switch in the cockpit. In order to turn off "ACARS" the person may have to open the trap door outside the cockpit and pull the fuse or circuit breaker under the plane's belly. It requires deep knowledge of the Boeing 777 in order to pull off something like that.

On Monday, Ahmad said, "Initial investigations indicate it was the co-pilot who basically spoke the last time it was recorded on tape."

Police raided the homes of pilot Zaharie Ahmad Shah and co-pilot Fariq Abdul Hamid on March 15. The investigators have recovered a home-made flight stimulator from Zaharie's place.

Acting Transport Minister Hishammuddin Hussein replied to a question related to pilot suicide.

"Yes, we're looking at it."

He mentioned that he "cannot say for the moment" if the pilots faced any personal or financial problems.

Leaked Footage of MH370 Pilots

Recently, leaked footage that showed Malaysia Airlines flight MH370 pilots - Zaharie and Fariq going through security checks at the Kuala Lumpur Airport has gone viral on the Internet.

The footage is taken from closed-circuit television video showing Captain Zaharie and co-pilot Fariq going through the routine checks. Later, they collect their bags.

The footage is no longer available on line.