Jamesh Murmu, who was booked under various sections of IPC including murder and was incarcerated in the Dumka Central Jail since August 2011, was taken for production in the court of District Judge Virendra Pratap Singh.
However, when as he was being taken back to jail, he consumed something in the van and started vomiting, said Dumka Central Jail Jailer U N Gupta.
He was immediately taken to the jail cell and given treatment by the doctors, who referred him to Dumka Sadar Hospital.
It could not be ascertained what he has consumed, he added.