Alternate Interior Minister Christos Markoyiannakis yesterday invited representatives of all political parties to attend a debate on illegal immigration on Wednesday after police staged a sweep of the capital’s historic center where derelict buildings are home to thousands of migrants. By late yesterday, the main opposition PASOK and the far-right Popular Orthodox Rally (LAOS) were reported to have accepted the invitation to the debate. Measures heralded earlier this week by the government, including an intensification of policing in the capital as well as on the borders, are expected to start bearing fruit in about a month, sources said yesterday. MPs in the ruling conservatives’ camp are reportedly divided over how strict the measures should be. Prime Minister Costas Karamanlis is expected to stress the growing pressure faced by Greece as the European Union’s southwestern gatekeeper at a scheduled EU summit in Brussels next week. Meanwhile in Athens, where a large proportion of migrants end up, police sources told Kathimerini that a proper crackdown will only be possible once the temporary reception centers that the government has promised are up and running. «The centers must be prepared and then we can proceed with an operation to arrest the majority of illegal immigrants,» a senior police official said. His comments followed a police sweep in central Athens late on Thursday that led to the arrest of 52 people after inspections on 580. According to sources, only five of those arrested were illegal immigrants. Police responded that they had not been targeting migrants but crime in the broader area. Nevertheless, sources said that rumors of the impending police sweep resulted in many would-be migrants abandoning their squats, including some 600 immigrants occupying the premises of the old Athens appeals court on Socratous Street.