Lucknow, Sep 3 - Five people, among them a doctor and the leader of the gang involved in a large-scale racket in sale of adulterated blood, were arrested here Thursday, the Uttar Pradesh police said.

Those arrested were identified as gang leader Alok Dwivedi, U.B.Singh, a doctor at the state government's Balrampur Hospital, and Izhar, Pushpendra and Raman.

Six people, including an anaesthetist from the same hospital, were arrested Aug 22 for the racket that was allegedly being run in connivance with several well-known private blood banks and doctors.

'The arrests were made from different localities today after we got vital clues from the interrogation of the six people arrested earlier,' Additional Superintendent of Police Vinay Chandra told IANS.

Several raids have been conducted at private hospitals and blood banks and notices have also been served by the Food and Drug Authority to nearly half a dozen hospitals, pathological laboratories and blood banks, police officials said.

'Dr. U.B. Singh also runs a private nursing home, Umrai Hospital, in Ashiana locality and it was the first hospital raided by health and police officials', Chandra added.

Earlier, the Sanjay Gandhi Post-Graduate Institute of Medical Sciences (SGPGIMS) revealed in its reports that the adulterated blood recovered from the accused was infected with the Hepatitis B and C virus - raising the scary possibility that a number of patients might have already contracted the infection.