The group called for a thorough investigation into the death of John Villanueva Jr. of Albay radio station dzGB last Monday and the wounding of Davao Citys Juan "Jun" Pala in an ambush.
Villanueva, 53, was shot dead while riding a motorcycle on his way home after anchoring his radio program.
Pala, 48, had also come from his morning radio program on dxGO and was aboard a taxi along with three bodyguards when van-riding men fired at them.
Pala was hit in the buttocks. It was the second attempt on his life; the first was on June 14, 2001. He now travels with bodyguards.
The Paris-based Reporters Without Borders urged the government to "end the cycle of violence against journalists and the impunity that routinely protects their aggressors."
Pala, known for his criticism of communist insurgents in the South, survived the ambush after his three bodyguards fired back.
Villanueva, a former three-term vice mayor of Camalig, Albay, was suspected of supporting the countrys communist guerrillas, although it was unclear whether this had anything to do with his killing.
The New York-based Committee to Protect Journalists (CPJ) said it was investigating whether the attacks were related to the two broadcasters work.
The Albay-Legazpi City chapter of the Kapisanan ng mga Brodkaster ng Pilipinas (KBP) has sought the help of the National Bureau of Investigation (NBI) to look into Villanuevas killing.
"Give justice to the family of our slain colleague," Rodgie Abril, the groups president, said in his radio program yesterday.
Pala himself has demanded a probe by the NBI or the Criminal Investigation and Detection Group, saying he no longer trusts the Davao City police.
About 39 journalists have been murdered in the Philippines since democracy was restored in 1986, making the country one of the most perilous in the world for members of the media, according to the CPJs annual report released this month. Celso Amo, AFP