Greece resumed during the weekend large-scale round-up operations of illegal migrants across Athens, as authorities increased border controls fearing a possible influx of Syrian refugees.

Approximately 5,000 persons have been detained over the weekend and 1,130 were arrested as undocumented illegal immigrants to be deported, according to a Greek police announcement.

The new operation, code-named "Xenios Zeus" in a reference to the hospitable father of gods in Greek mythology, was the first major sweep operation since last spring before the general elections in Greece.

Greek people could no longer afford the supplementary heavy burden of thousands illegal migrants amidst the acute debt crisis that threatens the country with bankruptcy, Greek officials said.

Greek minister responsible for public order Nikos Dendias and Greek police spokesman Christos Manouras stressed in statements that similar operations would continue to restore regality.

Greek officials have linked the presence of hundreds thousands illegal migrants over the past few years in Greece with increased rates of lawlessness, from prostitution, drug trafficking to armed burglaries with casualties.

Greece has become a major gateway for immigrants from Africa and Asia who try to reach other European Union member countries.

According to official estimates, more than 100,000 people have been entering Greece illegally on an annual basis over the past decade, in particular from the north-eastern borderline with Turkey.

Fearing a possible influx of refugees from unrest-hit Syria, Greek authorities have decided to deploy more guards to the area in coming days and weeks.