Far-right group the English Defence League has "completely questionable" tactics, its leader has admitted.
Tommy Robinson said "the non-Muslim working class don't have a voice" and warned "it's not going to end pretty".
It comes after heightened tensions in the wake of the killing of Drummer Lee Rigby in Woolwich, south-east London, with an increase in the number of attacks on mosques and Islamic centres.
Mr Robinson denied his group was behind a blaze at an Islamic centre, which was daubed with the letters EDL, in London's Muswell Hill last week.
He told the BBC Radio 4 Today programme: "If something was set fire and someone wrote David Cameron on the side of it, does it mean he did it?
"It just seems ridiculous to me and I think everyone can see through it that that's done to make it look like the English Defence League. If I'm honest, I'm completely sceptical that it is even non-Muslims that have done that."
Asked if he would condemn attacks by his members on Muslims, he replied: "Utterly condemn it, disgraceful. Every single speech I gave since Woolwich, in fact in the last four years, condemn any acts of violence. So the only way to solve this is through democratic process, through peacefully protesting."
He added: "Our tactics are completely questionable, yes, and I understand people who say you are going about it the wrong way, but what choice do we have as working-class people, who, as soon as you put your head above the parapet, you call a racist or a fascist? Who wants to sit down and talk to us?"
Asked if he condemned any EDL member who gave a Nazi salute, he said: "Well, I think if I was standing next to them there'd be a violent act. If you look into our history, I was actually arrested for assaulting someone doing that at our demonstrations."
Shaista Gohir, who chairs the Muslim Women's Network UK, told Today: "When the Woolwich attack happened, that weekend Muslim Women's Network got about 19 calls from Muslim women across the country. A lot of it was verbal abuse; also intimidation while driving, which could lead to accidents. It was food and drink being thrown at them. The insults were really awful, mums with their children. Definitely the incidents are getting worse."