Afghan authorities say they have detained a police chief in connection with last year's killing of five aid workers from the Doctors Without Borders group.

An Afghan interior ministry spokesman said the police chief of Qadis district of Badghis province is a suspect and has been detained for questioning.

Three foreign and two Afghan aid workers were killed when their vehicle was hit by grenades in an apparently targeted attack in Badghis June 2 last year.

A month later, the Nobel Prize-winning medical relief agency pulled out of Afghanistan after 24 years, citing poor security and the government's failure to launch a "credible" investigation into the killings.

Some information for this report provided by AFP and Reuters.