Contaminated intravenous fluid is suspected in the deaths of 12 pregnant women at a government hospital in northwestern India, police and health authorities said Friday.

Doctors are battling to save the lives of four more women who fell critically ill after being given the fluid in the maternity ward, hospital superintendent Narendra Chhangani said.

Police are investigating the manufacturer and distributors of the tainted IV fluid after the young women died over the past 10 days in the state-run Umaid hospital in Jodhpur, a city in Rajasthan state.

Authorities have seized the remaining bottles of fluid in the hospital after laboratory tests confirmed that some of the bottles were contaminated, a police official said.

"The hospital administration has banned purchases from the manufacturer of the glucose and the company has been asked to withdraw its IV fluid stocks from all over the country," said inspector general Bhupendra Dak.

Initial tests showed that the glucose supplied to the hospital were tainted with bacteria and fungus, Dak said.

Health authorities were also inspecting the hospital's operating rooms and the maternity ward for infectious bacteria as part of their investigations, he said.

Rajasthan's health minister A. A. Khan said the government was awaiting the results of glucose samples sent for further tests to a laboratory in Calcutta and those responsible for the deaths would be punished.

Tens of thousands of women die in India each year during pregnancy or childbirth because of limited access to emergency care.