A VIOLENT gunman and drug dealer, one of a gang of nine men convicted last week, was previously charged with assaulting Celtic skipper Scott Brown and also with shooting one of his friends. Mark Richardson, a member of the notorious Daniels Glasgow crime gang, pleaded guilty to a reduced charge of having a Glock handgun. He had been charged with shooting rival Lyons gang enforcer Ross Monaghan and Robert Kelbie, Brown's friend and an adviser when he was transferred from Hibs to Celtic for £4.4 million in 2007.

Richardson, a former Hibs casual, was a boyhood friend of Brown's but the two fell out badly in an alley outside the Edinburgh nightclub Citrus in 2009. Richardson was charged with a vicious assault on the Celtic player but these charges were subsequently dropped. However Kelbie, a former boxer, hunted down Richardson and beat him up.

Weeks later Richardson was arrested and charged and subsequently sentenced to 10 years for drug dealing. In October 2010 Kelbie was shot in the back outside Bannatyne's health club in Edinburgh, following the beating up with baseball bats of Richardson's father, also Mark, less than 24 hours before.

Richardson was released from jail in 2014 and the bitter feud continued. Last year Kelbie's house was shot up and he then went into hiding. The two came to blows once more when Richardson and Kelbie, by then a convicted mortgage fraudster, decided to have a "square go" at a funeral at Portobello Cemetery last April.

The nine Daniels gang members and associates all pleaded guilty to reduced charges in the High Court in Glasgow last week. The Daniels, originally from Glasgow's Milton estate, have been at war with the Lyons, from nearby Possilpark, over control of the drug trade. In 2001 a large stash of Daniels' cocaine was stolen from a house in the Milton and sold on to the Lyons.

The war has been marked by repeated attacks and shootings. One of the most notorious and bloody incidents occurred in early December 2006, in Lambhill at Applerow Motors, owned by David Lyons, brother of the head of the clan, Eddie Senior. It was like a scene from a gangster movie, one witness said, but it was being played out for real in north Glasgow. Two men in long black coats, wearing masks and holding handguns walked into the forecourt and started shooting.

It was over in minutes but when the smoke cleared Lyons' 21-year-old nephew Michael was dead on the ground, his cousin Steven was badly wounded, as was Robert Pickett, known as Piggy, who hadn't long come out of prison for the attempted murder of fellow drug dealers, the Rennie brothers, in the Paisley drug wars. Two Daniel gang members were later given life sentences for the Applerow murder and shooting spree.

The Daniel's chief enforcer, Kevin "Gerbil" Carroll, a pal of Richardson's, was shot dead in the Asda car park in Robroyston, Glasgow in January 2010. He was notorious as the head of the so-called alien abduction squad, which kidnapped and tortured rival drug dealers who, perhaps unsurprisingly, claimed to have no memory of it when questioned by police later.

The Gerbil had been shot twice before. Lyons' alleged trigger man Monaghan was charged with murder but the case against him collapsed in court through lack of evidence after witnesses withdrew statements – and despite his DNA being found on one of the murder weapons. A Lyons associate, William Paterson, was convicted.

Last January Monaghan was shot and wounded (and not for the first time) as he took his child to school at St George's Primary in Penilee, Glasgow. The gunman, head and face swathed, arrived at the school pushing a buggy, before opening file with a 9mm pistol. It was for this shooting that Richardson was charged.

Another of the Daniel's gang was a former soldier also allegedly involved in the Monaghan shooting, Martyn Fitzsimmons. He was jailed in 2008 for 12 years for smuggling a massive army arms cache from Canterbury barracks – including high-powered guns and ammunition – to Carroll and the Daniel's gang. At the time he was a lance corporal in the Royal Regiment of Scotland (Argyll and Sutherland Highlanders).

Last week Fitzsimmons pleaded guilty to the reduced charge of having a Glock pistol and hiding £36,000 of drug money. Other members of the gang of nine pleaded guilty to serious charges including discharging a firearm, abduction, torture, supplying cocaine and being involved in "serious organised crime". They were all remanded in custody and will appear in court again later this month.