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The search for the mastermind behind last week's terror attacks in Paris has led investigators to the Molenbeek neighborhood in Brussels, Belgium. 

The largely Muslim area has become one of the world’s main breeding grounds of violent Islamist extremists and has been dubbed by some as "the terror capital of Europe."

Fox News foreign affairs correspondent Benjamin Hall traveled to Molenbeek and spoke to some residents who supported the deadly terror attacks as fair retaliation for the coalition bombings in Syria and Iraq.

Hall reported that up to 500 Belgian jihadis have traveled to Syria and Iraq, the highest percentage in Europe, with more than 130 returning.

"It must be said that the majority of people here condemn the attacks," Hall said. "But there is certainly a dark undercurrent of radicalization in this country, as through much of Europe, and the authorities seem powerless to stop it."

Watch more above.

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