The incident happened at around 6.58 AM when a stray horse was hit by an unidentified car on the Red Road, following which it died on the spot, a senior officer of Kolkata Police said.
The driver fled from the scene but was later detained and was found to be a juvenile, he said.
As per law, matter is being referred to Juvenile Justice Board and a case was indexed against him under IPC Sections 279 and 429.