STOCKHOLM, March 21 (Xinhua) -- Three cases of bird flu have been reported since the first case was identified on Danish shoreslast week, according to reports reaching here from Copenhagen on Tuesday.

    Scientists confirmed that a dead swan found in Frederikssund, 30 km northwest of Copenhagen, was contaminated with bird flu.

    The Danish Veterinary and Food Administration established a three-kilometer security zone prohibiting poultry production, among other things, around the area where the swan in northern Zealand was found.

    An additional 10-kilometer surveillance zone was also set up that stretched from Roskilde in the south to the northern coast ofZealand.

    The dead swan marked the third case of bird flu announced in Denmark within a week.

    Laboratory results could not verify whether the swan had been infected by the deadly H5N1 subtype of the virus.

    The two discoveries of bird flu in the past week both containedthe H5N1 subtype. A buzzard found on Svinoe, south of Copenhagen, marked the first discovery of the disease, while nine tufted duckson the island of Aeroe off the coast of Funen marked the second. Enditem