Pakistani authorities say gunmen on a motorcycle have killed three Chinese engineers and their Pakistani driver in the troubled southwestern Baluchistan province.
Local police say the drive-by shooting occurred Wednesday in a remote town southeast of the provincial capital, Quetta.
The Associated Press says a tribal militant group, the Baluchistan Liberation Army, claimed responsibility for the attack.
In a separate development, in the North Waziristan tribal region bordering Afghanistan, Pakistani security forces arrested two men late Tuesday on suspicion of links with al-Qaida.
Pakistan's army has conducted a series of counter-terrorism operations in North and South Waziristan in the past three years, aimed at trapping Arab, Afghan and Central Asian militants with links to the Taliban and al-Qaida.Some information for this report was provided by AFP, AP and Reuters.