Eight women have died and 20 others are in a critical condition after undergoing sterilisation surgery as part of a free government-run programme to help slow India's population growth.
A total of 83 women, most of them poor villagers, had the operation in a hospital outside Bilaspur city in the central state of Chhattisgarh on Saturday, according to the district magistrate, Siddharth Komal Pardeshi.
The women were sent home in the evening following their operations, but more than two dozen were later rushed to private hospitals by ambulance after falling ill. Eight of them died, Mr Pardeshi said.
"They have all had the same symptoms," including low blood pressure, headaches, breathing problems and signs of shock, said Arvind Gupta, the director of Apollo Hospital, one of the facilities where the sick women were taken. Post-mortem examinations were being performed on those who died.
The state has suspended the three government doctors who performed the surgery, Mr Pardeshi said. It also will give compensation payments of about $3,300 to each of the victims' families.
India's government - long concerned with fast growth in a country whose population has reached 1.3 billion - offers free sterilisation to both women and men who want to avoid the risk and cost of having a baby, though the vast majority of patients are women.
In many cases, they are offered a one-off payment for undergoing surgery of about $10-$20 US, or about a week's pay for a poor person in India. Hundreds of millions of Indians live in poverty.
It was not immediately clear whether the women in Bilaspur were paid for undergoing Saturday's operations.
India has the world's highest rate of sterilisation among women, with about 37 per cent undergoing such operations, compared with 29 per cent in China, according to 2006 statistics reported by the United Nations. In 2011-12, the government said 4.6 million Indian women had been sterilised.
While India's central government stopped setting targets for sterilising women in the 1990s, activists such as Brinda Karat, of the All India Democratic Women's Association, say state governments still set sterilisation quotas which lead health authorities to coerce patients into surgery rather than advising them on other forms of contraception.
"These women have become victims because of the target-based approach to population control," Ms Karat told reporters, while demanding that the state's health minister resign.