Assistant Inspector K Satishan, part of an excise team on a routine vehicle check, was bitten on his left ear by the man and had been hospitalised.
The excise team was on a routine vehicle check when they signalled an autorickshaw in which two persons were travelling, to stop but it did not.
After a chase, the officials intercepted the auto and found 240 bottles of IMFL, being brought from neighbouring Mahe, an enclave of Union Territory of Puducherry in Kerala.
Sathisan was admitted to the Medical College Hospital here where he would undergo a plastic surgery, doctors said.
Police arrested the two persons.