The fighting between the Bani Hilal tribesmen and Nubian villagers in the southern province of Aswan was ongoing and the death toll is expected to rise, the officials said.
On Thursday, the rival sides attended a reconciliation meeting aimed at ending long-standing disputes, but an argument broke out and became a firefight that killed three tribesmen, the security officials said.
Tribal vendettas are common in the rural and poor south, but this week's violence is the worst in recent memory, they said.