Egypt’s interior ministry announced late Wednesday that a total of 444 Muslim Brotherhood members were arrested during the two-day constitution referendum.
The ministry accused the anti-referendum protesters of attempting to disrupt the voting process. Officials confiscated birdshot rifles, bladed weapons and molotov cocktails.
Those arrested will be referred to the public prosecution, added the ministry's statement.
The constitutional poll took place on Tuesday and Wednesday, 14 and 15 January.
At least nine were killed on Tuesday in nationwide clashes between Muslim Brotherhood members, local residents and security forces.
The new constitution, if approved, will replace the Islamist-drafted 2012 charter.
According to the post-June 30 political roadmap, a successful referendum will be followed by parliamentary and presidential elections within the next six months.