New Delhi (PTI): Clashes between CPI(M) and Sangh Parivar outfits in faraway Kerala on Sunday had violent fall-out here when RSS-BJP activists attacked the marxist party central headquarters triggering a battle between the rival sides that left 15 people including five senior CPI(M) leaders injured.

In the presence of BJP leader Jagdish Mukhi, the saffron activists pelted stones at A K Gopalan Bhavan, the CPI(M) central office, on Bhai Vir Singh Marg near Gole Market in the heart of Delhi when a Central Committee meeting of the Left party was on, police sources said.

CPI(M) workers retaliated and in the clash that erupted activists of both sides were injured. Among the CPI(M) activists injured are five central committee members two of whom Joginder Sharma and Hari Singh Kang were hospitalised.

Police lobbed teargas shells to disperse the warring activists.

Windows of the CPI(M) office were broken and the ground floor of the multi-storeyed building which houses the office of the party organ "People's Democracy" suffered extensive damage.

Window panes of a number of cars, including that of CPI(M) General Secretary Prakash Karat and Polit Bureau member Sitaram Yechury, were smashed during the violence.

The party suspended its Central Committee meeting and held an urgent Polit Bureau meeting to discuss the situation arising out of the attack by the saffron workers.

Fifteen people were arrested in connection with the violence, police sources said.

The CPI(M) has lodged an FIR with Delhi police accusing Mukhi and Delhi mayor Aarti Mehra among others of being responsibile for the attack on its office.

While the CPI(M) claimed that about 16 of their activists were injured, the RSS said 20 of their workers were hurt.

The Rapid Action Force was deployed after the clashes.

Reacting to the attack on the CPI(M) headquarters, party Polit Bureau member Sitaram Yechury alleged "the RSS was trying to spread the culture of terror in the national capital as they were doing in Kerala".

He alleged the police did not make adequate security despite knowing that there would be protests on Sunday.

An array of senior Congress leaders, including Delhi Chief Minister Sheila Dikshit, Tourism and Culture Minister Ambika Soni and AICC spokesperson Veerappa Moily visited the CPI(M) headquarters and condemned the attack on it.

The BJP said it will raise the political violence in Kerala's Kannur district, where CPI(M) and RSS-BJP activists had been battling against each other for the last three days, in Parliament on Monday even as the RSS warned it will not tolerate attacks on its workers and will take the marxist party head-on.

RSS leader Ram Madhav alleged that in the last five days "Marxist goonda elements" resorted to violence in Kannur killing five BJP-RSS activists and seriously injuring dozens of workers.

"When our members were peacefully demonstrating outside the Marxist party office, Marxist elements displayed their fascist attitude like in Nandigram and Kannur," he said.

Madhav claimed around 20 people were injured in the attack which further shows Marxist party's scant respect for democracy.

"The RSS cannot be cowed down by violence. We will take it head-on. We only want to ask Kerala government to take immediate steps to restore peace and don't expect us to take it lying," Madhav said.

Karat said UNPA leaders, who are meeting in Jaipur, rang him up and condemned the incident and expressed solidarity with the CPI(M).

CPI Secretary D Raja, who is in Bhubaneswar, spoke to Karat and Yechury on the phone and condemned the incident.

Among the other leaders who condemned the incident were TDP leader Chandrababu Naidu, Railways Minister Lalu Prasad and Chemicals and Fertilisers Minister Ramvilas Paswan.

Accusing the attackers of having a "fascist" mentality, Paswan demanded a high-level inquiry as the attack was "pre-planned and happened in the heart of the capital".