A single gunshot fired from a passing car blasted the window of a ground-floor home in Royston Mains Gardens on Thursday night.
No-one was injured in the attack, which is believed to be linked to a violent battle for control of the local drug trade among gang members.
Neighbours said one of the occupants, a man in his early 20s, was a known associate of gang leader Marc Webley, 20, who was sentenced to 11 years in November for the shooting of rival Peter Simpson.
Simpson, 46, was jailed for six years earlier this month at the High Court in Edinburgh for a brutal knife attack on Webley cohort James Tant, 22, on board a bus.
With both ringleaders in jail, it is thought that gangs are now engaged in a bitter fight for control of the lucrative drug trade in their absence.
It is the second time the windows of the Royston flat have been smashed by gunshots following an earlier shooting in July 2004.
That incident was also linked to the bitter feud between Webley and Simpson which saw escalating bloodshed during a year-long confrontation.
Police were called to the flat at around 8pm on Thursday after neighbours witnessed the shooting. They described seeing a car speed away from the scene after the shot had been fired from the passenger side.
Forensic officers were yesterday carrying out ballistics checks on the bullet which was fired into the living room of the flat.
Detectives carried out interviews on neighbours in the block of flats while the three people believed to stay in the home were also questioned at Drylaw police station. The road on either side of the flat was sealed off by police until 6pm yesterday after officers had kept guard outside throughout the night. Patrol cars also monitored the area during the early hours.
Council workers were sent to the home yesterday to board up the broken window.
One resident in Royston Mains Gardens said: "This is the second time the flat has been shot at. I was told a Kalashnikov rifle was used the first time. This is a drug thing between gangs in Royston and Wardieburn about who is the main man in different areas. With Webley and Simspon in jail, they're all trying to take control."
Another resident said: "My neighbour was the one who called the police. She was at her window when she saw a car stop and a shot was fired before it sped away. She was frightened out of her wits.
"Five police cars arrived and there were officers everywhere.
There were police cars going up and down the road all night."
The latest incident has led to concerns among residents that they are about to witness a return of the earlier drugs war where petrol bombs, knives, crossbows and sawn-off shotguns were used by gangs.
In the days after Simpson's conviction, Superintendent Terry Powell, who led the police operation against the ringleaders, warned that gang members from both sides of the feud remain at large and urged the community to help prevent a repeat.
Mr Powell said that the trouble originally flared when a new generation of criminals came up against the old guard in Granton, Royston, Pilton, Wardieburn and Drylaw.
On one side were the "Young Mental Royston" members fronted by Webley - a thug with more than 60 convictions - who harboured ambitions to establish himself as the crime kingpin of the area.