B. Singh, a practicing pathologist in the state government's Balrampur Hospital.

Fresh raids in Lucknow were conducted at many hospitals, including Era Medical College, and the renowned Kohil Pathology and Blood Bank that has two branches in the city. Although the result of investigations at these two places is yet to be revealed, similar anomalies are expected to surface.

A couple of years ago, the Aliganj police raided Kohli Pathology lab and arrested over two dozen professional blood donors, of whom most were drug addicts and rickshaw pullers. The lab was sealed and remained closed for over a year.

Besides the Chhatrapati Shahuji Maharaj Medical University (CSMMU), the names of some high profile private hospitals have also come to light for their alleged involvement in the blood racket.

'Besides blood, we also recovered pouches of plasma from their hideout where they collected blood. It is impossible for an untrained person to extract plasma from blood and the involvement of some doctors and pathologists has also come to light,' Chandra added.

'Earlier, they used to buy empty blood bank wrappers from the CSMMU at a cost of Rs.100 per piece. A few months ago, they started getting the wrappers printed in a printing press in Basti district. Besides private hospitals, the name of some private blood banks have also come to light and more arrests are expected soon,' Chandra said.

He said police had clues that some prominent private blood banks in Aliganj, Vikasnagar, Mahanagar areas of the capital and around the CSMMU campus were also involved in the racket.

The CSMMU vice-chancellor has admitted the racket has been going on for long.