A second day of clashes between two tribes in southern Egypt has left a total of 18 people dead, officials say.
The Egyptian military said that it had intervened to stop the fighting between the Arab Bani Hilal clan and a Nubian family.
The violence started late on Friday after offensive graffiti was drawn on the walls of a local school, security officials said.
Several homes were burnt down and over 31 people were injured in the clashes.
Eyewitnesses reported seeing bodies lying on hospital floors, while images emerged on social media showing bodies in the street.
A meeting on Saturday between leaders from the two sides failed to reach a resolution.
The state news agency said 17 local schools would be closed on Sunday, the first day of the working week in Egypt.
Police failed to intervene to put an end to the violence, prompting the armed forces to step in, according to eyewitnesses.
It is not known what sparked the graffiti war that led to the latest bloodshed.
There has been tension in the past between Arab clans and ethnic Nubians, who originate from southern Egypt and north Sudan.
However, this incident is the most serious instance of ethnic bloodshed in recent years.