Pakistani security forces say they have arrested a tribal militant commander suspected of involvement in the killing of three Chinese engineers in the southwestern province of Baluchistan.

Security officials say the suspect is a local leader of the Baluchistan Liberation Army and wanted in other attacks in addition to the February killings of the Chinese workers in the town of Hub.

On Tuesday in Baluchistan, unidentified gunmen killed a local politician and his bodyguard and injured a third man.

Police say Abdul Samad Achakzai and his bodyguard were killed when gunmen fired on their car as it drove through Kojak pass, northwest of Quetta, the capital of Baluchistan province. The third man, identified as Sulaiman Shah, was seriously wounded.

Police say Achakzai was one of the leaders of a Pashtun ethnic political group, Pashtoonkhwa Milli Awami, that is linked to a local tribal feud.

Some information for this report was provided by AFP and Reuters.