Indian police are investigating whether 30 infants died for lack of oxygen in a northern state-run hospital, the second case within a month in which medical supply shortages have been blamed for the deaths of dozens of children.

An underfunded, poorly managed public health system is in the spotlight after more than 60 children died in August in a public hospital in northern Uttar Pradesh, amid accusations that oxygen supplies ran out because of unpaid bills.

The infants died of "perinatal asphyxia" at the newborn care unit of the hospital in the state's Farrukhabad district between July 21 and Aug. 20, police said.

The investigation suggested that 30 of a total of 49 children died of perinatal asphyxia, police added in the complaint, seen by Reuters. This condition is caused by a reduced level of oxygen in infants just before, during or after delivery, depriving them of the ability to breathe freely.

A district magistrate on Wednesday ordered the inquiry into the deaths of the infants, after media reports linked some deaths to oxygen shortages. He also ordered action against all the doctors involved in the deaths. The district's chief medical superintendent, Dr Akhilesh Agarwal, denied there had been any lack of oxygen. The hospital saved 121 of the 145 infants admitted in critical condition following their birth elsewhere, he added. "The rest died since their conditions were critical," he told Reuters.

Nineteen more babies were born dead in the government hospital, and the six remaining, from the tally of 49 in the government report, died of unspecified causes, he added, without elaborating.