The families of victims of the MH370 plane tragedy have marked the fourth anniversary of the aircraft's disappearance. The memorial comes as Malaysian officials say the search for the flight will likely end in June, after extensive investigations.

IT’S the mystery that still has the world holding its breath - just what happened to missing Malaysia Airlines flight MH370?

Now, an Australian mechanical engineer claims to have tracked it down near Mauritius, and says the public is being kept in the dark by authorities.

Peter McMahon, who has reportedly worked in crash investigations for more than 25 years, has been hunting for MH370 ever since it disappeared in 2014.

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McMahon, 64, says he has finally found what he believes is the jet using NASA and Google Earth images and has pinpointed its location to 16 kilometres south of Round Island, north of Mauritius.

It’s an area that’s not yet been searched by investigators.

In one of the images, the outline of part of an aircraft is visible just below the surface of the water, the UK’s Daily Star reports.

In another, what appears to be a piece of the front cabin can be seen south of Rodrigues Island, also close by.

He claims to have sent his evidence over to the Australian Transport and Safety Bureau (ATSB), which has confirmed it could in fact be the missing plane.

However he alleges that US officials refused to search the area and are hiding information.

“Four Americans were sent to Australia to oversee the findings of MH370,” he said. “They have made sure that all information received has been hidden from the public, even our government - but why?

“...(they) do not want it found as it’s full of bullet holes, finding it will only open another inquiry.”

Malaysian Airlines Flight 370 vanished from radar en route from Kuala Lumpur to ­Beijing on March 8, 2014. No distress signal or message was sent and all 239 passengers and crew on the Boeing 777 are presumed dead.

The aircraft is believed to have made a radical change of course less than an hour after it took off and crashed in the ocean off Western Australia six hours later.

news.com.au has contacted the ATSB.