A "paranoid" party-goer who smashed a pint glass into a teenager's face during an unprovoked attack has been jailed for three years.

Gavin Andrews caused permanent scarring to his 18-year-old victim, who needed more than 20 stitches to wounds by his left eye and elsewhere on his head.

Sentencing the 20-year-old to a young offender's institution, Judge David Morton-Jack described the attack on Andrew Chung as "a horrible offence".

"'Glassings' are horrific. They can blind, scar dreadfully and lead to death," he said.

Andrews, of Geoffrey Barbour Road, Abingdon, has a previous conviction for theft. He had punched and kicked a foreign student before stealing from him.

Oxford Crown Court heard on Friday, August 17 that Andrews had been found guilty of causing grievous bodily harm with intent against Mr Chung after a trial in July.

A jury had heard trouble flared during a party at the Guild Hall, Abingdon, last November.

Andrews, who has a young son, had drunk between 12 and 15 pints that evening and believed Mr Chung had been threatening and mocking him during the evening.

But Judge Morton-Jack told Andrews: "You were very, very drunk indeed and, as so often happens with very drunk young men, your mind turned to violence.

"You own witness during the trial pointed out that paranoia often affects the very drunk - he thought that you were paranoid."

Mr Chung had told the court that Andrews at first headbutted him on the top of the nose by the dance floor.

The teenager then retaliated with one punch. Witnesses told the court Andrews than stepped back, picked up the glass and smashed it into his victim's face.

Andrews had glassed Mr Chung by accident, saying he punched Mr Chung but forgot the glass was in his hand.