Egypt's Minister of Interior Mohamed Ibrahim has warned that any attacks on the ballot boxes following the end of the constitutional referendum would be met with strict reactions, in a televised interview aired on a satellite channel on Tuesday.
Ibrahim accused the Muslim Brotherhood of attempting to disrupt the voting process, which is taking place under security control.
He threatened that anyone who thinks of "approaching the ballot boxes would be shot with live ammunition."
Egyptians started voting on a draft constitution on Tuesday in a referendum seen by the interim government as a stepping stone towards democracy, but by Islamists, who will boycott it, as illegitimate.
Egypt's army has promised intense security of the two-day voting process, in cooperation with the police.
Parliamentary and presidential elections are expected to kick off after the referendum, but in which order they will be conducted is yet to be decided.
Many violent confrontations erupted on Tuesday between security forces and supporters of the Brotherhood, which left at least nine people killed and 28 wounded.
The Interior Minister said that the clashes have pushed the ministry to change its security plan and deploy more forces.
"The high voter turnout drove the Brotherhood insane," Ibrahim added.