A senior government official said the cabs were impounded by the enforcement wing of the department.
Yesterday, the government had directed transport department to take strict action against those companies that are charging fares more than prescribed rates during the odd-even car rationing period.
"We have so far impounded 25 cabs which belong to different companies including Ola and Uber. The violations include driving without fitness certificate, bagde, uniform and others. Also, there were several permit violations," the official said.
Ola and Uber had yesterday suspended 'surge pricing' after Chief Minister Arvind Kejriwal ordered strict action, including permit cancellation and impounding against overcharging by taxis.
Surge pricing is a technique used by Uber and Ola to raise fares to provide drivers the incentive of keeping their cab running while also making it available for the user irrespective of the demand.