The Kerala Police on Sunday detained five more people in connection with the murder of a Rashtriya Swayamsevak Sangh (RSS) worker here yesterday.
Earlier in the day, three people were taken into police custody in connection with the case.
The State Police Chief said, the Police forces have been instructed to strictly deal with any attempt to create violence and adequate force have been deployed in all sensitive spots.
He also appealed to social media users to restrain themselves from spreading rumours and provocative messages, which would attract legal action.
Earlier on Saturday, an RSS worker was murdered in Thiruvananthapuram's Sreekaryam.
The Bharatiya Janata Party (BJP) has alleged Communist Party of India (Marxist) CPI (M) workers behind it.
On July 11, an RSS office at Payyannur in Kannur was attacked allegedly by CPI (M) workers.
No one was inside the office at the time of the incident.