The West Bengal Health Department has barred 11 blood banks from organising blood donation camps across the state until further notice while investigating allegations of serious irregularities, including the illegal sale of blood collected in West Bengal to other states. The probe is being conducted by the State Blood Transfusion Board following allegations that some blood banks illegally sold blood and plasma collected in West Bengal to other states for financial gain. A notification issued by the Health Department states that the ban on organising blood donation camps came into effect from August 1. Sources said some blood banks had organised donation camps without obtaining the required permission from the Health Department. Authorities said no new blood donation camps will be permitted for the 11 blood banks until the investigation is completed.