Badal Chowdhury was taken to a hospital and his condition was stated to be stable.
The opposition CPI(M) on Wednesday alleged that its Central Committee member Badal Chowdhury was attacked by "BJP-sheltered goons" in South Tripura district.
Mr Chowdhury, the deputy leader of the opposition in the state assembly and former minister, was injured and his vehicle was damaged in the attack, the party said in a statement.
Local BJP leaders denied the charge while the police said the matter is being investigated.
The CPI(M) said that the incident occurred when Mr Chowdhury and other party leaders were holding a programme to observe the death anniversary of Dhananjay Tripura, a Kokborok language movement martyr, at Manirampara village, around 110km from Agartala.
A group of BJP sheltered goons reached the spot on motorbikes and launched an unprovoked attack on them injuring Chowdhury, the Left party said.
Mr Chowdhury was taken to a hospital and his conditionwas stated to be stable.
The CPI(M) took out a rally in Agartala in protest against the alleged attack.