Ten people belonging to BJP and RSS were taken into custody in connection with the hurling of a bomb near the venue of a public meeting of CPI(M) state secretary Kodiyeri Balakrishnan.
While CPI(M) alleged that BJP and RSS were behind the incident, the saffron party refuted the charge, saying the Left leadership was trying to spread "fake news" and create tension in the district.
Police said no untoward incident was reported from any part of the district and the situation was now under control.
Patrolling and searches have been intensified in the district, which has witnessed frequent clashes between BJP-RSS and CPI(M) workers after the May 16 Assembly polls last year that saw LDF coming to power.
"Ten people belonging to BJP and RSS were taken into custody in connection with the incident that took place last night at Nangarathupeedika in New Mahe area of Kannur. Patrolling has been intensified in the area," police said.
In retaliation, BJP offices at Nadapuram and Vadakara in neighbouring Kozhikode district were vandalised, allegedly by CPI(M) activists, after the incident.
To condemn the attack on its party offices, BJP observed a dawn-to-dusk hartal in the area on Friday.
A local BJP panchayat president was allegedly manhandled in a scuffle between the CPI(M) and BJP workers during the hartal, police said.
Reacting to the incident, Kodiyeri Balakrishnan said it was "pre-planned to create provocation".
CPI(M) veteran V.S.Achuthanandan alleged that the BJP and RSS, "under the shadow of the Narendra Modi government", were repeatedly trying to create tension through provocation.
"All those who value democratic principles should come forward and be vigilant against this attitude of Sangh Parivar forces," the former chief minister said, adding there should not be any lapse on the part of police to bring to book those responsible.
Denying the allegations, BJP state president Kummanam Rajasekharan said CPI(M) was unleashing large-scale violence in the district by spreading "fake news" of bomb hurling near the venue of Balakrishnan's meeting.
"Nine BJP-RSS offices were attacked by the CPI(M) yesterday. The left party should withdraw from its attempt to create tension in the district on an issue in which BJP-RSS has no role," he said.
Opposition leader Ramesh Chennithala also condemned the bomb hurling incident and appealed to both parties to eschew violence.
On January 18, a 53-year-old BJP worker was stabbed to death at Andaloor in Dharmadam, the constituency of Chief Minister Pinarayi Vijayan. Six CPI(M) workers were arrested in this connection.