A doctor who performed sterilization procedures on nearly 83 women in central India, leading to the deaths of at least 13 women, has been accused of using unauthentic medicine and rusty surgical equipment, Reuters reported Wednesday. The medical procedures, conducted at an annual "family planning" camp on Saturday, also left 20 women in critical condition.

Officials in the central Indian state of Chhattisgarh, where the deaths occurred, reportedly said that preliminary reports reveal that there were signs of toxic shock but the cause of death was yet to be determined. Nearly 52 women were admitted to hospitals in Pendari village in Bilaspur district after the doctor reportedly performed surgeries on more than 80 women in a span of only six hours. A police complaint was lodged against the doctor by the local government, accusing him of negligence.

"Preliminary reports show that the medicines administered were spurious and also the equipment used was rusted," a senior local government official told Reuters.

Local governments in India frequently set up sterilization camps as a means to provide affordable birth control to the country's poor. Local media reports said that the women who underwent surgery at the clinic on Saturday were given nearly 700 rupees, or $11 -- a significant sum in rural India -- as compensation. But, such drives have been criticized by rights groups.

"The payment is a form of coercion, especially when you are dealing with marginalized communities," Kerry McBroom, from the Human Rights Law Network in New Delhi, said, according to ABC News.

The state health department has reportedly ordered an inquiry into the incident while a team of doctors from New Delhi arrived in the village to investigate the case, which has reportedly triggered outrage in the region.

While the Congress party called for a state-wide strike on Wednesday, the main opposition party also demanded the resignation of the state's health minister and its chief minister. On Monday, four health officials, including the chief medical health officer of Bilaspur, were suspended, according to local news reports.