The incident happened yesterday under Kotwali Police station area in the old city here, police said.
Zubair was sitting outside his hut when a pig pounced on him and caught him by his throat killing him on spot, police said.
The protests were triggered by reports that pigs owned by residents of a nearby Valmiki locality were often straying into neighbouring localities and causing a menace.
The mob indulged in brick-batting and pelted stones at a police outpost leading to injuries to at least three policemen.
An FIR has been registered against the protesters, police added.
