A GERMAN UFO expert has claimed that a NASA spacecraft may have been hijacked by aliens - who are now attempting to contact the Earth.

Hartwig Hausdorf claims that Voyager 2 - an unmanned interplanetary probe blasted into space 33 years ago - has started transmitting strange, unintelligible signals, Bild newspaperrevealed today

NASA installed a 12-inch disk containing music and greetings in 55 languages in case intelligent extraterrestrial life ever found it.

But last month the probe began sending back distorted messages from its location near the edge of the solar system that baffled NASA scientists were unable to decode, Mr Hausdorf says.

"It seems almost as if someone had reprogrammed or hijacked the probe, thus perhaps we do not yet know the whole truth," the author of UFOs - They Are Still Flying told Bild.

The signal from Voyager 2 - which takes 13 hours to reach the Earth - broke off fully on April 22.

NASA said engineers were working to solve a data transmission fault.

The space agency has not commented specifically on Mr Hausdorf's comments, although it says the fault is likely to be a glitch in the probe's computer memory

Voyager 2 and its twin, Voyager 1, were launched in 1977 to explore Jupiter, Saturn, Uranus and Neptune. Three decades on, they are the most distant human-made objects in outer space.

Voyager 1 is currently more than 8.5 billion miles from Earth. It will soon travel beyond the heliosphere - a bubble the sun creates around the solar system - into interstellar space, scientists say.

Originally published as NASA spacecraft 'hijacked by aliens'