A quadruple stabbing and a shooting that happened less than a mile from each other on consecutive days are believed to be linked by the police.
Four men, all in their 20s, were stabbed in north London shortly before 6pm on Sunday, with three remaining in hospital on Monday morning, although their condition was not disclosed.
Police were called to reports of a fight in Fraser Road, Edmonton and two vehicles that had been in a collision were found at the scene.
The stabbings came around 24 hours after a boy and two men suffered injuries when a shotgun was fired at a minicab less than a mile away. A Scotland Yard spokesman said: "At this early stage, officers believe the incident is linked to the shooting in Gordon Road, Enfield on Saturday, November 17."
One person has been arrested and police are continuing with their enquiries.
At the scene of the shooting, a 16-year-old boy and two 22-year-old men were found with injuries.
Police believe the group were in a minicab when a second vehicle pulled alongside the car while it was stationary.
"At least two men got out and approached the victims. One was armed with a shotgun. The shotgun was fired twice into the rear of the vehicle," the Met said.
The men escaped life-threatening injuries, although one of the passengers' injuries are thought to be "potentially life-changing". The minicab's driver was not injured.
Police have appealed for witnesses or anyone with information to come forward.