The accused, identified as Ritesh Maratha (30), was being held in the Palasia police station lock-up after he was nabbed on July 24, said SP (East), OP Tripathi.
In the morning yesterday, Maratha said he was feeling sick and wanted to vomit, following which the guard on duty brought him out of the lock-up.
But as he was being escorted back to the cell, Maratha allegedly pushed the policeman and ran out of the police station and escaped, Tripathi said, adding that head constable Vijay Singh was suspended with immediate effect for alleged negligence.
Maratha and his associate allegedly duped bank customers of about Rs 20 lakh by withdrawing money from their accounts through fraudulent means.