Reporter: Riots on the streets of Antwerp as hundreds of North African Muslims clashed with police. They're furious about the murder of a 27-year-old Moroccan teacher gunned down by an elderly white Belgian in an apparent racial killing. Crowd: [inaudible] Reporter: This is the man whose name they shout. [Dee-ab-ood-jah-jah], the charismatic, articulate 31-year-old who's honing and sharpening Muslim anger as leader of a new militant group called the Arab European League. Speaker 3: These police corps here in the city is infiltrated by the far right [inaudible]. We don't trust them. They have racial abuse, they have police brutality. They have militance of [inaudible] who go to the meeting [inaudible] at night, and the morning, they go and put their uniform and they carry a gun and they go on what they call [mah-kah-kah] hunt, which is, [mah-kah-kah]'s a white ape. Reporter: Do you think there are racist elements within the city police force in Antwerp. Speaker 4: Of course. That's like everywhere. I don't think that the police is, like the society, there are racists in the society. There also will be in the police force. Reporter: At city hall the following day, civic leaders condemn [ah-boo-jah-jah] for the violence and announce a greater crack down on M who commit crime. Sitting at the table, uncomfortable with their spin on events, is a shaken young man name [Sah-teev=ack-rag]. It was his brother who died yesterday. "My brother, who was hit once in the head and once in the side, died in the arms of my other brother who just came from school. What happened yesterday is clearly pure racism, but we ask all the community to live with us, and we hope there will be no misuse of this incident." But that seems a vain hope in a place where the flames of racial tension are regularly fanned for political advantage. Filip DeWinter is no friend Belgium's 400,000 Muslims. The leader of the far right [fams-block] party, he has won wide support here, preaching fear and hate. [crosstalk] at the last mayoral elections, one in three Antwerp voters chose Filip DeWinter's politics as their own, and this is what he thinks about [aboo-jah-jah] and his religion. Filip DeWinter: Don't be naïve about Islam. Don't be naïve about that religion. It's an offensive, very dangerous religion who is not at all compatible with our way of life, with our values, with those things who are really important for us. Speaker 3: They do not want us as partners. They want us as subject. Then, of course, they have a problem with us. At first, they try to marginalise us to say that we don't represent anybody. The, they see that we represent a lot of people, so they try to criminalise us. If people are shooting Moroccans in the street here, I will not be the one saying, "Don't shoot back." Speaker 6: [inaudible] Reporter: This is the most controversial of [ah-boo-jah-jah's] initiatives. Late night street patrols by members of the Arab European League. Listen to the politicians and the media here, and this represents the start of lawlessness and vigilantism. But, Ahmed [Ah-soo] says the AEL is just keeping a watching eye on the Moroccan community and those white police men who stop Moroccans in the street. Speaker 6: They have that mentality of superiority, even worse. Every that goes wrong here; it's our fault, really. So, that's not a good way of trying to have a healthy community in Antwerp. Reporter: Most of these young men are the children of guest workers who came to Antwerp more than a generation ago to do the dirty jobs Europeans were no longer prepared to do, but unlike their parents, they're not grateful or silent. They believe they're discriminated against in the workplace, at school, and on the street. And, [ah-boo-jah-jah] is galvanising their frustration. Speaker 3: When I get 100% of my rights. I'm no thankful. I'm not grateful. I will say, "Well, it's about time that I get them," and I expect a little bit of Mea culpa of the 20 or 30 years that I haven't been getting these. Reporter: The Belgium government might want the Arab European league banned, but its leader is fast becoming a Muslim folk hero. After his arrest, [ah-boo-jah-jah] spent five days in jail, but a judge declared there was no evidence it incited the violence at the Antwerp riots. Now, the Arab European League wants to contest Belgian election later this year. The big question is, will those in power acknowledge its right to do so, to try to criminalise it further? The rest of Europe will be watching closely. Speaker 3: I think we are a test for democracy in this country. Reporter: Might you be a martyr for your cause at some point? Speaker 3: Nobody wants to die, you know, or wanna be in prison. Nobody likes that. Now, if you ask me if you prepare to do that for what you believe in, yes. Speaker 4: It should be a very bad thing if he should come in parliament. I think we have to do something now. Don't wait until it's a bigger movement. We have to do it now and tell those people, "Look, if you want to integrate, you're welcome. If you want to be happy with everybody else, you're welcome. But if you want to create an Arab Islamic State, go to Arabic Islamic State." Speaker 3: Do they want the Arab European League that is doing on the elections, that may be radical but that is democratic? Or do they wanna forbid the Arab European League? They wanna eliminate it and then create a phenomena like the IRA or the [ETA] in Belgium. Do they want that? It's their choice.