MAZAR-I-SHARIF, April 18: A knife-wielding attacker on Sunday killed three Afghan policemen at their headquarters in the northern city of Mazar-i-Sharif, police said.

"An unknown attacker using a knife has killed three police including the provincial police operations director in the police headquarters," duty officer Mohammad Zaman said.

Police were investigating the case and have arrested one person in relation to the incident. "Only one suspect had been arrested and we don't yet know if it was private enmity or an act by terrorists," he said. "The investigation is going on."

There has been repeated fighting between rival militias in the north but this is believed to be the first attack in a police headquarters in Mazar, capital of Balkh province. -AFP