What is a Hit and run case in motor accident?

Regret unable to answer this question as the term seems unfamiliar to me, but I expect that it may be realted to motor claims conditions and appreciate your calrification after you obtain the answer.

 Thanking You

All vehicles are supposed to take motor third party insurance.This is a social obligation of the Government making TP insurance compulsory for all vehicles.

At times, some accidents occur in which one of the vehicle/s involved in the accident escapes from the site of accident without a prima facie evidence of the identity of the vehicle that caused the accident. This called Hit and Run case.