Egypt's police have tightened security measures in the capital Cairo and all squares nationwide in anticipation of Muslim Brotherhood protests, Al-Bawaba News reported Friday. Security checkpoints have been set up near the capital's entrances and outputs following calls by the Brotherhood group, that is designated as terrorist by authorities, for its loyalists to stage violence and riot, police said. Police crackdowns have been staged against terror cells hideouts in the capital and tens of terrorists have been arrested, police added. Police stressed all governmental institutions and foreign facilities have been under close protection.