At least four children died and four fell ill after a vaccination drive in Jharkhand’s Palamu district on Sunday, The Indian Express reported.

Unidentified officials said the vaccination drive took place on Saturday afternoon at Loinga village. At least 11 children were vaccinated at the local Anganwadi Centre by an auxiliary nurse mid-wife, the daily said.

According to district officials, the children developed fever, diarrhoea, and vomiting in the hours that followed, and by Sunday morning, four of them died. Soon after, angry villagers blocked the roads and also detained the nurse and Block Development Officer who came to the village after getting information about the deaths, IANS reported.

“From an initial inquiry, it does not seem that the vaccine was past its expiry date,” Palamu Acting Civil Surgeon, Vijay Kumar Singh, told The Indian Express. Meanwhile, Principal Secretary (Health) Nidhi Khare set up a team, which would be assisted by doctors from the World Health Organisation and United Nations Children’s Fund representatives, to find out what caused the deaths.

Jharkhand Chief Minister Raghubar Das has also ordered an inquiry and announced Rs 1 lakh each as compensation to the deceased’s families.