Four policemen, including two sub-inspectors, were suspended on Thursday over the escape of a NSCN (IM) insurgent in Manipur, police said.Twenty-three-year-old Thailik Panmei escaped from a lock-up of Imphal police station on Wednesday morning. The police are carrying out extensive operations to arrest him and an appeal has been made to the public to share information. A cash reward of Rs 1 lakh has also been announced.Other than the two sub-inspectors the suspended police include one assistant sub-inspector and a head constable.“Three village defence force personnel have also been disengaged for dereliction of duty. A DIG level officer has been entrusted to enquire into the incident of the escape,” a police officer said.On July 6, Thailik Panmei was arrested during an operation by security personnel in Manipur’s Noney district. He was lodged in the lock-up of Imphal police station from July 7 after being produced in the court.