Col. Ahmed Ali said the men were carrying automatic rifles, machine guns, explosives and police uniforms, Ahram Online reported. Three trucks and nine motorcycles Ali said had been used in clashes with the army and police were confiscated.
The Muslim Brotherhood has consistently denied any connection to attacks on government security forces. The government declared the organization a terrorist organization in December.
A spokesman for the Health Ministry said one person was killed and five others injured in clashes Friday in Cairo and other parts of Egypt, al-Masry al-Youm reported.
The incidents occurred as the Muslim Brotherhood staged protests in several parts of the country.
The Interior Ministry said a 29-year-old Brotherhood member was arrested in the coastal governorate of Damietta after he was found with 15 firebombs during a march.
The deaths of a 42-year-old man and a 12-year-old child during a clash with security forces was blamed on the Muslim Brotherhood.