A combination photo shows drawings with messages of hope for passengers of missing Malaysia Airlines Flight MH370 at Kuala Lumpur International Airport (KLIA)
A combination photo shows drawings with messages of hope for passengers of missing Malaysia Airlines Flight MH370 at Kuala Lumpur International Airport (KLIA) outside Kuala Lumpur June 14, 2014. Sunday marks the 100th day that the flight from Kuala Lumpur to Beijing disappeared with 239 passengers and crew on board. REUTERS/Samsul Said

More than four months have passed and Malaysia Airlines flight MH370 remains missing and the mystery behind its disappearance remains unsolved. Many theories emerged claiming the probable cause of the tragedy. However, none provided a definite answer. Meanwhile, sister of Captain Zaharie Ahmad Shah has finally spoken up in defence of her brother, who was reported to be considered the "prime suspect" in the police investigation of the missing jet.

On July 13, Channel News Asia reported that the sister of Captain Zaharie Ahmad Shah has "broken her silence" while speaking on the channel in Channel NewsAsia's special feature "The Mystery of MH370". According to the report, this is the "first ever interview" that the Captain's sibling appeared on after MH370 went missing. The show focused on the events of March 8, the night when Malaysia Airlines flight MH370 disappeared with 239 people on board.

Following the investigation, Captain Zaharie came under the suspicion of investigators. It is thought that if the plane disappeared due to human intervention, Captain Zaharie could be the man involved in the activity. The report notes that Captain Zaharie's sister, Sakinab Ahmad Shah "rejects the notion that her brother was responsible" for the tragedy.

To support her notion, Sakinab Zaharie said: "We couldn't figure out why somebody who would want to commit suicide would prolong the agony of flying for four, five, six hours just to land down there."

According to the data by the investigators, MH370 kept flying for over six hours after disappearing from radar detection.

"If it was done, if he was the one who planned it, he has to be some kind of Einstein, which he was not," Sakinab Zaharie added.

During the investigation, investigators found some flight simulators that only added to the suspicion surrounding Captain Zaharie. However, his sister explains that Captain Zaharie was "just a man who took so much to aviation."

"He loved aviation, he spent a lot of his funds buying model airplanes. If he could, I think he would attach wings to himself and fly -- he loved flying that much," Sakinab Zaharie Ahmad Shah further explained.

Earlier, The Sunday Times reported (via Daily Mail) that the checks have cleared all the people on board missing Malaysia Airlines flight MH370, except Captain Zaharie. After finding "suspicious evidence from a flight simulator in his home," Captain Zaharie was considered the "prime suspect" in the investigation. The web site reported that the 53-year-old Captain practiced operations including take-offs and landings on isolated locations using his simulator. This simulator also included landing strips in the Southern Indian Ocean, which is thought to be the resting place of missing Malaysia Airlines Flight MH370.

Adding to the suspicion was the lack of "social or work-related future commitment" made by Captain Zaharie, unlike his colleagues. After conducting the focused investigation on Captain Zaharie and 170 interviews by the detectives, the investigators arrived at the said conclusion centering on Captain Zaharie's involvement. However, investigators haven't ruled out the possibility of mechanical failure or act of terrorism that may have resulted in the mysterious disappearance of MH370.

Malaysia Airlines flight MH370 was travelling from Kuala Lumpur to Beijing when it went missing. No debris or traces related to the missing Boeing 777 have been discovered to date. The case remains the biggest mystery in the aviation industry, and remains unsolved even after four months.

For more updates and information on the missing Malaysia Airlines flight MH370, read below:

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