Police said seven international shipments had been intercepted during the investigation. Detectives believe stolen vehicles were being exported to the Democratic Republic of the Congo.
Officers from the Force Intelligence Branch and Tactical Aid Unit carried out warrants at three residential addresses and a storage unit in north Manchester and Oldham on Wednesday 4 November.
The searches took place at Middleton Road in Oldham and St Augustine Street, Foynes Close and Kingsbridge Road in Harpurhey.
Two men in their 30s, a man in his 40s and a woman in her 30s were arrested on suspicion of conspiracy to steal motor vehicles and conspiracy to handle stolen motor vehicles.
All four remained in custody for questioning at the time of the announcement.
GMP said the 19 recovered vehicles were suspected to be linked to the group under investigation.
Detective Chief Superintendent Lewis Hughes, who heads the Force Intelligence Branch, said, “Every stolen vehicle has a victim behind it. A family unable to get their children to school, a worker unable to earn a living, a business disrupted.”
He said around 5,000 vehicles were now stolen annually across Greater Manchester, compared with more than 8,000 six years ago.
“The individuals involved in organised vehicle crime often believe they are one step ahead, but we will continue to use every tactic available to identify offenders and recover stolen vehicles.”
