Detectives investigating the deaths of two eastern European men five miles apart have said they cannot rule out "a potential organised criminal element".
A 35-year-old man was found dead in undergrowth on Hogg Lane, Elstree, at about 15:40 GMT on Friday.
At 20:30 the previous day, a 30-year-old man was found stabbed in the boot of a car near Scratchwood Park, Barnet.
A 31-year-old man at the scene was arrested on suspicion of murder and is in custody.
Det Ch Insp Simon Stancombe, from the Met Police, said: "While we retain an open mind as to a motive, we cannot rule out whether there might be a potential organised criminal element.
"We also believe that the two victims might have been known to each other."
Police were called shortly after 20:10 to reports of a fight in Courtland Avenue, Barnet, but found no victims or suspects.
The man in the car was found about 15 minutes later and died a short time afterwards.
The 31-year-old man at the scene was initially taken to hospital with injuries before being arrested.
The second victim was found in a remote lane about five miles (8 km) from where the first man discovered.
Officers are working to establish how long the body had been there and whether his death occurred before or after the discovery in Barnet.
Investigators have asked residents who might have any information or footage to come forward.
Det Ch Insp Stancombe added: "I am asking those residents who live in the vicinity of the crime scenes in Barnet and Elstree to think very carefully about anything suspicious you may have seen over the last few days, and to make contact with us immediately.
"It could be that you may have caught something via dashcam footage that could prove massively important. The slightest fragment of information could prove crucial."