The mother of a man who was killed by a single punch has said she wants young people to realise "you just need one punch to end a life".
Andrew Molloy, 25, was fatally injured in an attack outside the Old Mess House pub in Oldham on 15 March.
Louis Veitch, of Blackpool, admitted manslaughter and was jailed for six-and-a-half years in September.
Now Mr Molloy's mother, Jackie, is backing a police campaign to combat alcohol-fuelled violence.
Launching their One Punch Can Kill campaign, Greater Manchester Police (GMP) said alcohol-fuelled violence claimed the lives of 13 people in the force area in the past five years.
'Fists are weapons'
Men aged 18 to 25 are the most likely to commit and be victims of serious violent crime, the force said.
About 40% of victims of violent and serious violent crime are young men and the vast majority of offenders are men.
"It is not publicised like the gun crime and knife crime. You don't really hear about it," Ms Molloy, of Hathershaw, Oldham, said.
"We had not really heard about it until it happened to us.
"Fists are a weapon. You can kill somebody".
Mr Molloy suffered serious head injuries when he was punched and fell into the road in the early hours of 15 March.
Moments earlier, Veitch, 22, of Caunce Street, Blackpool, had told onlookers: "You might think I'm a short fat muppet but I've got a killer punch."
Mr Molloy, who had previously tried to act as a peacemaker between Veitch and another man, was taken to the Royal Oldham Hospital and transferred to Salford Royal, but died six hours later.
"That was it - with just that one punch", Ms Molloy said.
She said her son's death had affected the family "in every way shape and form".
She added: "We still get up in the mornings hoping that he will walk in."
Ms Molloy, 48, said she believed young people did not realise how powerful a punch could be.
"They need to realise the consequences.
"You really don't need to batter somebody, you just need to punch them once and you can end a life."
GMP Assistant Chief Constable Garry Shewan said: "It only takes one punch to kill someone and destroy the lives of people's families.
"People who have had a drink do things they wouldn't dream of doing when they're sober and a stupid, split-second reaction can have devastating consequences.
"We're not trying to spoil anyone's fun but people need to realise that when you've had too much alcohol you leave yourself more open to becoming a victim of crime or getting yourself and others in trouble by behaving violently."
Officers are working with licensed premises, universities and taxi firms to promote the campaign.
Posters, window stickers and beer mats are being displayed in pubs, clubs and bars.