A bridegroom fatally shot his new wife, his best man and then himself after announcing to horrified guests that he had a "surprise" for them, Brazilian authorities say.

Police investigator Joao Brito said witnesses told officers that 29-year-old sales manager Rogerio Damascena did not give any previous indication that anything was wrong at his wedding reception in Rio de Janeiro.

Brito said on Monday that it was likely the slayings were premeditated because of the groom's announcement and because he had hidden a gun in his father's pickup truck.

The 25-year-old bride, Renata Alexandre Costa Coelho, and best man Marcelo Guimaraes were both killed in Saturday's murder-suicide.

A brother of the bride was treated at a hospital and released.

AP

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