Kanhaiya landed in the police net yesterday while his two associates are absconding, Senior Superintendent of Police Babloo Kumar said.
Sub-inspector Nand Kishor was found dead on July 18.
"Kanhaiya told investigators that Kishor neither fulfilled his commitment of getting marks of Surendra and Monu increased in their High School examination conducted by the UP Board nor he was returning the money given to him in advance," he said.
Kanhaiya, with his two aides, strangulated Kishor on July 15 at his Mallapura-based residence here," Kumar said.