The journalists were on their way back from the town of Sararogha, where they were covering the surrender of suspected tribal militant Baitullah Mehsud.
A car overtook the journalists' bus at around 7:30 p.m. near the town of Wana, and assailants opened fire with AK-47 assault rifles, according to The Associated Press, which quoted Mahmood Shah, chief of security for Pakistan's tribal areas bordering Afghanistan.
Anwar Shakir, a stringer for Agence France-Presse, was wounded in the back and is in stable condition, according to news reports. A fourth reporter, Zardad Khan, who was working for Al-Jazeera, was not seriously injured.
The Pakistani military has been cracking down on suspected al-Qaeda fighters in South Waziristan, a semiautonomous tribal region.