Bulgarian former PM Boyko Borissov in custody over corruption claims

A supporter of former prime minister Boyko Borissov wears a T-shirt demanding his release (AP Photo/Valentina Petrova)

Bulgarian ex-prime minister Boyko Borissov remained in custody on Friday following corruption investigations by European Union prosecutors as his supporters took to the streets to protest against his detention.

The Interior Ministry said late on Thursday that Borissov was being detained for 24 hours in a nationwide police operation that also targeted other former officials.