Update: A day after Nirmal was hacked to death, the police arrested five persons. According to the police, one of the accused Arun is a Yuva Morcha activist and all the arrested persons have been sent to judicial custody. 

A 20-year-old Yuva Morcha activist was hacked to death in Kerala’s Thrissur district in the wee hours of Monday, allegedly by CPI (M) workers.

According to the police, Nirmal was an active member of the Bharatiya Janata Party's youth wing. He was attacked by a group of unknown persons with a sharp weapon a little past midnight, while he was taking part in a festival at Kokkulangara temple in the district. 

Though Nirmal, who sustained grievous injuries, was rushed to a nearby hospital for treatment, he succumbed a few hours later.

At the time of the attack, Nirmal was reportedly accompanied by his friend Midhun, who is currently undergoing treatment.

Refusing to divulge details of the case, Mannuthy Sub-Inspector said that a murder case has been filed and that investigation is on.

Though the BJP in the district accused the CPI (M) of being involved in the murder, the police refused to confirm whether it was a case of political killing.

Meanwhile, the central district is observing a dawn-to-dusk hartal called for by the BJP on Monday.

Nirmal's death comes just weeks after a BJP activist named Ezhuthon Santhosh was murdered allegedly by CPI (M) workers in the politically sensitive Kannur district.