KUALA LUMPUR, Malaysia -- Investigators are trying to restore files deleted last month from the home flight simulator of the pilot aboard the missing Malaysian plane to see if they shed any light on the disappearance, Malaysia's defense minister said Wednesday.
Hishammuddin Hussein told a news conference that the pilot, Capt. Zaharie Ahmad Shah, is considered innocent until proven guilty of any wrongdoing. He said members of Zaharie's family are cooperating in the investigation.
Files containing records of the simulations carried out on the program were deleted on Feb. 3, Malaysian police chief Khalid Abu told the news conference.
Malaysia Airlines Flight 370 with 239 people aboard went missing March 8 on a night flight from Kuala Lumpur to Beijing. Malaysian authorities have not ruled out any possible explanations, but have said the evidence so far suggests the flight was deliberately turned back across Malaysia to the Strait of Malacca. They are unsure what happened next.
Investigators have identified two giant arcs of territory spanning the possible positions of the plane about 7 1/2 hours after takeoff, based on its last faint signal to a satellite. The arcs stretch up as far as Kazakhstan in central Asia and down deep into the southern Indian Ocean.
Police are considering the possibility of hijacking, sabotage, terrorism or issues related to the mental health of the pilots or anyone else on board, and have asked for background checks from foreign agencies on all foreign passengers.
Hishammuddin said background checks have been received for all the foreigners except those from Ukraine and Russia -- which account for three passengers. He said none of the checks has turned up anything suspicious.
Relatives of passengers on the missing airliner have grown increasingly frustrated over the lack of progress in the search after 12 days. Planes sweeping across vast expanses of the Indian Ocean and satellites peering on Central Asia have turned up no new clues in the hunt.
"It's really too much. I don't know why it is taking so long for so many people to find the plane. It's 12 days," Subaramaniam Gurusamy, 60, said in an interview from his home on the outskirts of Kuala Lumpur. His 34-year-old son, Pushpanathan Subramaniam, was on the flight heading to Beijing for a work trip.
"He's the one son I have," Subaramaniam said.
Meanwhile, CBS News' Seth Doane reports anger boiled over Wednesday morning as the Malaysian authorities prepared for their briefing.
Before Wednesday's news conference at a hotel near the Kuala Lumpur airport, Chinese relatives of passengers held up a banner and started shouting at the venue before police escorted them out.
© 2014 CBS Interactive Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.
