About 30 people were arrested in Hyderabad on Tuesday in connection with the alleged sale of plastic rice and eggs, and milk produced by buffaloes that had been injected with Oxytocin, a potentially harmful drug.

Residents at a hostel in the city’s Yousufguda area complained to officials after they were served plastic rice and eggs for dinner on Monday. Other complaints about plastic rice came from consumers in Srisailam in the Kurnool district of Andhra Pradesh. Fake rice is made by shredding chunks of plastic.

The Hyderabad Police Commissioner’s task force raided 15 dairy farms and arrested 20 people suspected of giving Oxytocin to buffaloes to increase their production of milk, according to reports.  Oxytocin, which is used to facilitate childbirth, has been linked to breast cancer, prostate cancer and male impotency.

Food samples were collected by investigating officials and sent to a lab to be tested.