A man found shot dead north of Adelaide earlier this month was the victim of a targeted execution-style murder, police have revealed.
Simon Middleton was found dead outside a property at Virginia with Detective Inspector Brett Featherby saying a number of people were now thought to be involved in the killing.
"The investigation has led us to believe that the premises where Simon was shot had been under surveillance," he told reporters on Monday.
"We are aware that a number of people had been involved in the planning of that murder.
"One man has engaged Simon in a conversation and then another has appeared and shot him."
Insp Featherby said detectives had searched eight properties and seized seven vehicles as inquiries continued but were not yet ready to reveal a possible motive for the attack.
"We believe we do have a motive ... but we need to keep an open mind," he said.
He urged anyone with information about the murder to come forward for the benefit of the 49-year-old's family.
Police also want to hear from anyone who saw a white Nissan Patrol in the area at the time, which is among the vehicles seized.