The worker, identified as Chandran, suffered injuries on his legs and was immediately admitted to a nearby hospital for treatment.
Earlier on November 19, another CPI-M worker was injured after a crude bomb was hurled at a rally.
CPI-M District Secretary Anavoor Nagappan alleged that the BJP workers had unleashed violence on the workers of his party during a procession.
However, in October, an RSS activist was injured, while bombs were hurled at a BJP party office.
Both left and the right-wing outfits in Kerala are accusing each other of the increased hostilities as the incidents of political violence are rising in the state. Kerala has a long history of political violence.
Police records of political murders between 2000 and 2017 question both the left and right-wing fronts.
In the last 17 years, 85 CPM workers, 65 RSS or BJP workers, 11 workers of Congress and IUML each have been killed.(ANI)