Three CPI(M) workers were injured when they were attacked in broad daylight allegedly by activists of radical outfit Popular Front at Mangalam near Tirur town near here today, police said.
According to police, the incident was sequel to a by-poll in a panchayat ward which the LDF had won.
Four persons had been taken into custody in connection with the incident, they said.
The LDF candidate defeated an independent backed by the Popular Front's political arm SDPI.
Chief Minister Oommen Chandy and Home Minister Ramesh Chennithala said police had been asked to tracked down the culprits without delay.
"We cannot allow these kind of incidents to repeat. We should not allow anybody to take law into their hands," Chandy told reporters in Thiruvananthapuram.
Meanwhile,CPI(M) state secretary Pinarayi Vijayan alleged that Indian Union Muslim League workers were also involved in the incident. Talking to reporters in Palakkad, he said SDPI candidate had the backing of the IUML also.
The SDPI and IUML leaders, however, distanced themselves from the incident.
The incident sparked widespread condemnation from across the political spectrum as Malayalam TV channels beamed visuals of the attack.
