Pakistani authorities on Wednesday said they were investigating the murder of six barbers in a tribal region that has long been a hotbed for militants looking to impose their version of strict Islamic law, which includes mandatory beards for men, Reuters reported. The six barbers were shot dead late on Monday night outside their residence in the North Waziristan district, and the killings have sparked fear amongst locals. "It is not yet known what the motives of this incident are, we are investigating," district police chief Rokhan Zeb Khan told Reuters, confirming that the six barbers had been shot in the head. The six, who ran different outlets offering grooming services, were not local residents and were living together close to their shops in the town of Mir Ali, where they were targeted by gunmen. Khan said the barbers were from neighboring province of Punjab. Previously outsiders have been attacked on allegations of being spies for Pakistan's security and spy agencies.