Thirteen children have died of a mysterious disease in Bihar's Muzaffarpur district during the past five days, officials said Saturday. Of these, five children succumbed in the last 48 hours.

"In the last five days, a total of 13 children have died of a mysterious disease and over 50 children have been admitted to different hospitals," a district health official said.

A.P. Singh, district civil surgeon, told IANS on phone from Muzaffarpur that the cause of the deaths could not be ascertained till now.

"We cannot say what disease led to the death of the children here. The disease is yet to be identified. Whether it is encephalitis or some unknown disease, we can say only after medical reports come," he said.

The district administration has sounded a high alert to check the spread of the disease. The children reported high fever followed by bouts of unconsciousness and convulsions leading to their death.

Local people termed the mysterious disease as 'chamki ki bimari' and claimed that the symptoms are similar to that of encephalitis, a disease that causes inflammation of the brain.

Official sources in the state health department here said there was no facility to identify encephalitis in Bihar.

Alarmed by a likely outbreak of suspected encephalitis, the principal secretary of health department Amarjeet Sinha Friday visited Muzaffarpur to take appropriate steps for the children afflicted with the mysterious disease.

He said that a team of doctors from Patna will Saturday collect samples for further investigation.