Benzes and a Land Rover belonging to suspected underworld kingpin Nafiz Modack and his co-accused were seized and taken to Cape Town central police station on Thursday for "investigation".
While Western Cape police spokesperson Lieutenant Colonel Andre Traut confirmed the seizure for investigation, he said the identities of the parties concerned could not be disclosed to the media.
News24 understands that police believe the cars were fitted with illegal gadgets.
Modack and his co-accused in an extortion case had appeared in the Cape Town Magistrate's Court, just metres away from the police station, earlier on Thursday morning.
Bulky men, who appeared to be their security detail, huddled closely around them.
Modack is accused along with Colin Booysen - the brother of alleged Sexy Boys gang boss Jerome Booysen - Jacques Cronje, Ashley Fields and Carl Lakay. They face extortion charges relating to nightclub security.
Irfaan Parker, for Modack, told Magistrate Joe Magele that some of his client's "security" was harassed outside the court building, and told that their cars were parked illegally, when they were not.
He said police officers had insisted that their vehicles be searched or that they be arrested.
"Clearly, there is no basis in law for that."
Modack and his co-accused, surrounded by men in dark clothing, stormed over to the police station after their appearance.
Modack sped off
It took around an hour for one of the vehicles, a Mercedes-Benz Vito van, to be released.
Modack then jumped into the car and sped off.
Traut confirmed that the van, a Land Rover and a Mercedes-Benz SUV were seized.
He said the driver of the Land Rover had been served with a suspension notice by the Cape Town Traffic Department.
"The third vehicle, a Mercedes-Benz SUV, will remain in our custody for further investigation. During the event, no one was arrested or charged."
Safety and security mayoral committee member JP Smith previously explained, in a statement on vehicle modifications, that a consistent number of vehicles had their roadworthy certificates suspended every year.
He said that national legislation required that modifications be done by a manufacturer or registered vehicle body builder. Once that was done, a vehicle had to be re-registered and sent for clearance to the South African Police Service, he said.
The case against Modack and his co-accused was transferred on Thursday to the Cape Town Regional Court.
They were expected to appear in that court on May 28.