The deployment is part of a massive sweep through the rugged desert region in search of people involved in a series of recent bombings, according to security officials.
 
Most of the arrests on Sunday took place in El-Arish, a north Sinai town close to the border with Gaza and Israel, a security official said on condition of anonymity because he was not authorised to issue public statements.
 
Earlier, another security official said special troops were preparing for a massive search for suspects in the region. "The forces ... will start combing the area tomorrow [Monday] morning."
 
Separate deployment

The open-ended manhunt is not connected with the deployment of 750 other Egyptian security forces which are taking up positions along the Gaza-Egypt border, in agreement with Israel as it abandons settlements in the Palestinian enclave.
 
Israeli forces have clashed often there with Palestinian arms smugglers and have destroyed dozens of smuggler tunnels.

A damaged van remains

Until last year, the Red Sea area, including Egypt's Sinai, had been free of extremist-inspired violence.

Beginning last October, however, the area has seen a string of deadly attacks that began at hotels in the Egyptian resort of Taba.

Last month, dozens were killed in three blasts that targeted Sharm el-Sheikh, the highly popular resort at the southern tip of the Sinai.
 
Last week a bomb in northern Sinai hit a vehicle carrying peacekeepers of the Multinational Force and Observers, which is helping monitor the 1979 Egypt-Israeli peace agreement.

Two Canadian soldiers were slightly injured.