A police officer walks next to a van during searches on Rue Delaunoy in Molenbeek late in January, 2017 | Filip de Smet/AFP via Getty Images Belgium’s Molenbeek home to 51 groups with terror links: report Police have checked on a quarter of all Molenbeek residents in past year.

A confidential report into anti-terror measures has revealed that police in the Brussels district of Molenbeek have uncovered 51 organizations with suspected ties to terrorism, local media reported Monday.

Police performed door-to-door checks and examined more than 8,600 houses and 22,668 inhabitants, a quarter of all Molenbeek residents, in the past year in a bid to improve security in Brussels.

Belgian Interior Minister Jan Jambon pledged to “clean up” Molenbeek, after authorities confirmed many of the suspects involved in the Paris and Brussels terror attacks either lived or operated from the area.

Of more than 1,600 organizations and NGOs registered in the neighborhood, 102 were suspected of having links with crime, and another 51 were linked to terrorism.

Authorities compiled a list of 72 individuals who ought to be monitored for their alleged terror connections. Of them, 26 currently reside in Syria and 46 in Belgium. Of those who live in Belgium, 20 are in prison and 26 are monitored closely.

According to the report, no one has left Belgium to join the fighting in Syria in the past 12 months.