A group of friends were attacked when they tried to stop a man being beaten up on Brighton Beach.

The victims were on their way home after a night out when they found a man on the mid level of Madeira Terrace being attacked by a gang of men at about 4.40am on Saturday, October 5.

They tried to stop the attack, but instead the 20-year-olds were themselves stabbed.

One suffered a stab wound to the hand, one a stab wound to the throat and the third a head injury after he was hit with a weapon.

The friends ran off towards Brighton Pier being chased by the offenders but were caught outside the Harvester restaurant in Marine Parade and the violence continued.

Detective Constable Paul Ash said: "This was a brutal attack that has left the victims with potentially life changing injuries. They were incredibly brave to step forward to help a stranger.

"There would have been a lot of people in the area at the time and I desperately want to speak to anyone who saw the incident or heard what happened as the violence spread from Madeira Terrace to Marine Parade. I would also encourage the man who was initially being assaulted by the offenders to contact us."

The first offender was white, 18 to 20 years old and at least 6ft tall. He was of muscular build, had dark short hair and was wearing a t-shirt which he tore during the attack. He had a tattoo on his upper chest.

The second offender was white, 17 or 18 years old, small and skinny. He had cropped hair.

The third offender was white, pale, about 18 years old and 5ft 9in. He had shaggy black hair and was wearing a t-shirt.

The fourth offender was white, 30 to 40 years old and had very short hair or was bald.

Anyone with information should call 101 quoting serial 300 of October 5 or the independent charity Crimestoppers anonymously on 0800 555111.