The boy studying in a private school did not return home after attending tuition last evening and is suspected to have been kidnapped, Inspector S Baskaran said.
A complaint in this regard had been lodged by the boy's father, he said.
The boy's parents had reportedly received phone calls from an unidentified person demanding a ransom of Rs 50 lakh for the release of the boy last night.
A case under IPC section 363 (punishment for kidnapping) has been registered, police said.
A special police team has been formed to trace the boy.