Arjun Singh was seen in a blood-soaked shirt and a bandage around his head.

BJP MP Arjun Singh suffered head injuries on Sunday afternoon, after police launched a baton charge to disperse party workers who had set up a road blockade at Kankinara in West Bengal's North 24 Parganas district. Arjun Singh, seen in a blood-soaked shirt and a bandage, claimed that the Barrackpore Police Commissioner had struck him while he and his party colleagues were protesting against the "capture" of a BJP office in nearby Shyamnagar.

"They attacked me and vandalised my car even though we were only protesting peacefully. Police Commissioner Manoj Verma hit me on my head, causing a huge gash. My residence is also being attacked," news agency ANI quoted Mr Singh as saying.

However, a senior police officer said that the politician was hit by a stone thrown during a clash between two groups in Kankinara. News agency PTI also quoted local sources as saying that the angry crowd blocking the road began throwing stones at police officers first, forcing them to retaliate with batons.

The BJP has called for a 12-hour shutdown, starting 6 am on Monday, to condemn the "attack" on its lawmaker.

After news of Mr Singh's injury spread, BJP workers gathered outside his house to protest. Police reached the spot, and a few of them were taken into custody. Police, however, did not give an exact number of those arrested. "We have to look at the figures," news agency ANI quoted Barrackpore Zone 1 Deputy Commissioner Ajay Thakur as saying.

JP Nadda, the BJP's national working president, accused the ruling Trinamool Congress of "murdering democracy time and again". "The attempt to capture the BJP office in North 24 Parganas district and the targeting of our MP, Arjun Singh, is highly condemnable. By resorting to such acts, the Trinamool Congress has been murdering democracy time and again in West Bengal," he said.

Both Shyamnagar and Kankinara come under the Barrackpore Lok Sabha constituency, of which Mr Singh is the MP. Several areas in the constituency, including Bhatpara and Kankinara, have witnessed violence ever since he quit the Trinamool Congress and won the recent Lok Sabha elections on a BJP ticket.

The politician's vehicle was vandalised near Shyamnagar Railway Station earlier in the day. A Barrackpore police officer said that unidentified people smashed the windows of his car, following which a complaint was filed. However, Mr Singh insists that Trinamool Congress workers were behind the incident.

According to PTI, Mr Singh also claimed that the ruling party was trying to capture BJP offices across Barrackpore constituency by force. However, West Bengal Minister Jyotipriya Mallick denied the allegation, instead accusing the BJP of indulging in such tactics. "Arjun Singh should remember what his people did to take over our party offices. Chief Minister Mamata Banerjee herself caught BJP workers red-handed while they painting a Trinamool Congress office saffron," he said.

(With inputs from Agencies)