A previously unknown piece by Mozart, believed to have been written when he was as young as 10, has been uncovered in Austria.

The piece, thought to have been composed in 1767 or 1768, was found in a notebook in an attic.

Researchers recently determined there was strong evidence Allegro Molto is a Mozart composition.

It was transcribed into a notebook bearing the name Del Signore Giovane Wolfgango Mozart.

Although the music was not written in the hand of Mozart or his father Leopold, historians at Salzburg's Mozarteum foundation strongly believe it is by the burgeoning composer.

Music expert Hildegard Herrmann-Schneider said only Leopold Mozart used this name when writing down his son's name.

The 160-page handwritten notebook, dated 1780, also contained musical works written by Mozart's father.

Austrian musician Florian Birsak performed the four-minute piece at Mozart's childhood home on his original piano.

He said: "It's not just anyone's piece, there is already a touch of the great Mozart he later became."

In 2009, researchers uncovered two pieces of music believed to have been written when Mozart was seven or eight.