At least 20 CPI (M) supporters were injured when a mob attacked a rally taken out by the party in South Tripura district.
The CPI (M) activists took out a rally demanding a probe into the Rafale deal when a mob attacked them.
The police immediately rushed to the spot and the attackers fled the spot.
The CPI (M) alleged that 'hooligans' of ruling BJP attacked the rally.
CPI (M) South Tripura district secretary, Basudeb Majumder, executive member of Tripura Tribal Areas Autonomous District Council (TTAADC) Parikshit Murasingh were among the injured.