BRUSSELS (Reuters) - More than 2,400 civilians have been killed in the southern Ukrainian city of Mariupol since Russia invaded the country last month, EU foreign policy chief Josep Borrell said on Monday.

       Borrell, speaking at a news conference in Skopje, said that more than 2.6 million people have fled Ukraine and the number of refugees could swell to 4-5 million.

       (Reporting by Sabine Siebold and John Chalmers)