Police found the body of another law enforcement officer in Laayoune.
Maghreb Arab Press (MAP) said that the caid sustained injuries in his stomach, face and in his back.
Authorities transferred the victim of the assault to the Sidi Othmane Hospital in Casablanca to receive necessary medical aid.
MAP added that the caid was in an inspection patrol against construction offenses.
When he attempted to stop a person, who started an illegal construction project, the man attacked the caid, stabbing him with the knife.
Police in the region opened investigation to clarify the circumstances of the incident.
MAP also announced today morning that Moroccan police in Moroccan southern city of Laayoune found the body of another Caid.
Local authorities said that the body of the deceased was marked with gunshot wounds. Police found the body of the law enforcement officer near a service vehicle that the victim had been driving.