The National Human Rights Commission (NHRC) on Thursday issued a notice to the Union health secretary on a complaint alleging that three big government hospitals in Delhi conducted illegal clinical drug trials on 3,479 children during the last five years.

The commission’s notice cited illegal clinical trials allegedly conducted on 2,056 children at Safdarjung Hospital, 1,023 children in Kalawati Saran Children’s Hospital and 400 children at Lok Nayak Jai Prakash Hospital.