Newly released documents revealed the last message sent to Malaysia Airlines Flight MH370's control display unit amid rumors of a massive cover-up. The message was reportedly sent four times but the delivery system never received a response signaling it had reached the aircraft.

"DEAR MH370. PLS ACK TEST MSG. RGDS/OC," the message read, with words like "acknowledge," "message" and "regards" being shortened.

The message was attributed to be sent by the operations center (OC) instead of the dispatch name. It was intended to be displayed in the cockpit on a CDU, which a pilot uses to perform tasks such as programming the flight computers.

The message was not received by the plane, and it is unclear why it was left out of the official documents until now.

Malaysia released a full report in July detailing the investigation into Flight MH370's disappearance. Investigators wrote in the report they were unable to determine what happened to the plane. However, the report claimed Flight MH370 deviated from its path not because of anomalies in the mechanical system or under autopilot but under manual control. It added investigators have not ruled out the possibility of a hijack.

With no additional details being provided, the families of those on board the plane criticized the report and accused the Malaysian government of a cover-up. There were also reports claiming data logs in the final report were incomplete and believed to be modified.

Following the condemnation, Malaysia’s Ministry of Transport last week released a 147-page report displaying the full log.

Malaysia Airlines said it had "provided full cooperation and assistance to all respective authorities."

Victor Iannello, who leads the Independent Group investigating the plane's disappearance, said some anomalies were found "in the message logs that were included in factual information released by Malaysia," as well as the safety report. The Independent Group had previously worked extensively with the Australian Transport Safety Bureau, which was leading the MH370 search.

"The new log confirms that there was a renewed attempt to initiate communications with MH370 at 18:38:51. The error messages that were generated confirm the link was not available at that time, likely because MH370 was not logged into ARINC’s server," he wrote.

Flight MH370 went missing March 8, 2014, with 239 people on board while on its way from Kuala Lumpur to Beijing. An extensive search of a remote part of the southern Indian Ocean yielded no concrete clues as to the plane's whereabouts.

As investigators are still struggling to find the plane's remains, several independent searchers are using Google Maps to locate the plane. In the latest claim, a British video producer said he spotted the doomed jet in a Cambodian jungle. To prove his claim, Ian Wilson will conduct a ground search with a team to find the plane.

Since the plane's disappearance, several conspiracy theories have emerged. Last month, a theory suggested Flight MH370 was most likely brought down by a stowaway on board the jet.

A woman leaves a message of support and hope for the passengers of the missing Malaysia Airlines MH370 in central Kuala Lumpur, March 16, 2014. Reuters/Damir Sagolj/File Photo