Security agencies are constantly reviewing arrangements at Red Fort and have zeroed in on the 'safe houses' where the Prime Minister and other leaders could be taken in case the need for the same arises, officials said. Visitors will not be allowed to carry mobile phones,cameras, binoculars, handbags, briefcases, cigarette lighters, transistors, lunch boxes, water bottles, lunch boxes, etc., to the venue and would be subjected to heavy security checks.