Two persons have been detained in connection with the incident, police said today.
Trouble started when the two groups first had a heated argument over some religious issue, which later turned into a furious fight in the Panchgate area of Mahuva town in Bhavnagar late last night, police inspector G G Bamania said today.
The two groups pelted stones on each other in which five persons sustained injuries, he said.
"When the rampaging mob started hurling stones at each other and burnt vehicles, we had to fire two rounds in the air and also lob three tear-gas shells to disperse the crowd," he said.
The Mahuva town police today detained two persons in this connection and started a further probe, he said adding that a case of rioting has been registered.