On a tip-off, Ballabgarh police raided the factory and seized printed labels of 20 known brands, 150 tins full of oil as well as several empty tins.
There were cemented tanks made in the premises in which the oil used to be mixed, SHO Ballabgarh police station, Sakir said.
He said the factory used to purchase oil from a company near Kurukshetra and then used to mix it with other oil of inferior quality.
Then the mixed oil used to be filled in tins and labels of popular brands pasted on them, police said, adding, the oil was then sold in the market at the rate of the brand.
The team of Food and Supply dept sealed the material found in the factory.
The owner of the factory Bhuvneshwar Kumar was not found in the factory, police said, adding, no arrests have been made so far.