A gunman killed three men and a woman at a shopping centre in the Finnish city of Espoo near Helsinki Thursday, dpa reported.
The man, still on the loose, was identified by police as being a a 43-year-old with a criminal record.
Witnesses said the man, dressed in black, fired multiple rounds from his automatic pistol, causing panic in the shopping centre.
Police released no initial information about possible additional casualties. A major police hunt was underway. Police had cordoned off and shut down the shopping centre.
Finland has suffered two major school shootings and a bombing in recent years.
In September 2008 a student opened fire in a vocational school, killing nine classmates and a teacher. The 22-year-old then shot and killed himself.
In late 2007 an 18-year-old student killed six fellow students, a nurse, and the headmaster, before shooting himself in the head.
After the most recent shooting, the Finnish government adopted tougher gun laws.
Espoo is the headquarters of mobile phone maker Nokia.