The murder of the worker, Remith at Pinarayi has sparked a slugfest between the CPI-M, which is heading the ruling Left Democratic Front, and the BJP.
Protesting against the murder, the BJP has called for a state-wide 12-hour hartal from 6 am on Thursday.
Remith, who suffered severe injuries on his head and neck in the attack that happened at 10.30 am, died on the way to hospital, police said. He was standing near a petrol pump when he was attacked, sending shock waves in the state.
"It looks like a political murder. The situation is now under control. Patrolling is on and efforts are on to keep things calm," said IGP-Northern Range Dinendra Kashyap.
Condemning the killing, BJP National President Amit Shah tweeted, "Attacks on BJP karyakartas in CM Pinarayi Vijayan's home constituency is a matter of grave concern and smacks of political vendetta".
"Chavassery Uttaman, Remith's father was similarly killed in 2002, his mother suffered serious injures when his house was attacked recently," Shah tweeted.
Vijayan, for his part, lashed out at the Rashtriya Swayamsevak Sangh for the growing violence in the state which he alleged was with the support of BJP government at the Centre.
Speaking at a function in Alapuzha, Vijayan hit out at the RSS and the BJP over the attack on a Marxist worker in Kannur two days ago and accused the RSS of spreading violence in the state.
"The attacks by RSS activists are increasing in the state. They are now showing more tendency of violence with the support of the BJP government at the Centre. They are committing murders and spreading lies and misunderstanding among people."
CPI-M general secretary Sitaram Yechury said the violence in Kerala has been started by the RSS-BJP combine itself and blaming the state's ruling party for the same is "total fabrication" of facts.
Blaming "political goondas" of the CPI-M for the murder, BJP spokesperson G V L Narasimha Rao demanded a Central Bureau of Investigation probe, saying it has no faith in the state police and the Left government.
The incident comes within two days of murder of a CPI-M activist and shop worker, Mohanan by a six-member gang at Pathiriyad in Kannur district, with CPI-M pointing fingers at the RSS for the attack.
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