Brazilian authorities say two police officers have been killed and five others have been injured in separate attacks in the slums of Rio de Janeiro.

The police department said a military police officer died and two others were wounded early Sunday in a gun battle with armed men in a hilly shantytown. The body of another policeman was found Saturday outside a health center with bullet wounds after it was apparently dumped there from a car. Three other officers were shot in three separate attacks over the weekend in a violent shantytown and near the city's port.

As the city prepares to host the 2016 Olympics, security officials are struggling to curb a wave of violence that left more than 100 officers dead last year.