Thiruvananthapuram, Nov 20 (PTI): Activists allegedly belonging to the BJP on Sunday 19 pelted stones at the CPI(M) district committee office here, even as clashes were reported in the district and in Kannur between workers of the two parties, police said.

The incident happened a day after Mayor V K Prasant was attacked allegedly by BJP workers at the city corporation council here. Four women councillors and a staff member were injured in the melee during a discussion on installing high mast lights in the city yesterday.

Seven persons have been taken into custody in connection with todays incident.

The window panes of the CPI(M) party office were damaged in the stone pelting incident, the police said.

A glass case in which the bust of late P Krishna Pillai, one of the founding leaders of the Communist movement in Kerala was kept, was also damaged, they said.

In Karikkam, two CPI(M) workers were injured in a clash and they have been hospitalised. CPI(M) district secretary Anavoor Nagappan alleged that BJP workers unleashed violence on the workers of his party during a procession tonight.

Minor clashes were reported between the workers of the two parties in Valapattinam and Iritty in Kannur district in which workers from both the parties were injured, according to police.

Devaswom Minister Kadakampally Surendran alleged that BJP and RSS workers were behind the attacks on CPI(M) activists.

Earlier today, Chief Minister Pinarayi Vijayan said the attack on Prashant was "well-planned" and led by BJP and RSS activists.

"The attack was deliberate and without any provocation," he said in a post on Facebook after visiting the mayor at the medical college hospital here.