Eleven babies died at the B C Roy Children's Hospital in Kolkata since Tuesday in a rerun of the 18 crib deaths in June there.
Six of the babies died on Tuesday and the remaining five on Wednesday, hospital Superintendent Dilip Roy said.
Roy said delayed admission of the babies who were already in a very critical condition led to the deaths.
"We are always trying to improve service and treatment but some deaths are taking place since the babies are being brought here at a critical stage," he said.
No complaint has been lodged, he said.
Family members of a six-month-old baby boy Abir Mondal from Kaikhali in South 24-Parganas district who died at the hospital demonstrated and blocked the road in the morning.
Hospital authorities, however, dismissed it saying, "some outsiders not known to the affected family tried to foment trouble in the hospital premises but normalcy was restored soon."
Chief Minister Mamata Banerjee had ordered an inquiry following the death of 18 babies at the hospital in June.
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