"On that night, in that place, they are probably safer than any other place they can be," said John Miller, head of the LAPD's new homeland security bureau.
Federal aviation officials banned planes from descending lower than 3,000 feet within three miles of Disneyland, a move they described as a precaution and not as a response to any specific threat.
Officials familiar with the security plans for the Academy Awards said more than 1,000 local, state, federal and private security personnel will be involved. Miller would not specify a number.
For the first time, the celebrities' televised arrivals on a red carpet will be eliminated, and Academy President Frank Pierson said Tuesday night that although there are no plans to postpone the event, that remains a possibility.
Officials said that also for the first time, closed-circuit cameras are in place so police can monitor all streets around the event site.
The cameras will cover "every square inch" surrounding the Kodak Theatre, said LAPD Capt. Mike Downing of the Hollywood Division. "Nothing will move inside or outside this theater without us knowing."
The 9th Civil Support Team from the National Guard, based in Los Alamitos, will be on the scene to lend support. The unit, which has been used at the Super Bowl and World Series, is trained to respond to chemical, biological and radiological attacks.
All hotel or hostel rooms overlooking the event have been taken by the Academy of Motion Picture and Sciences. Area buildings will be secured by Sunday, and law enforcement officers will patrol the rooftops -- steps officials described as comparable to those taken before a presidential visit.
Similarly, anyone entering the Kodak Theatre or standing along Hollywood Boulevard should be prepared to be stopped and searched -- regardless of how recognizable they are, officials said.
Searches will come on top of background checks FBI agents have conducted on virtually everyone with permission to enter the ceremony's immediate area, including limousine drivers and theater staff.
Police officers plan to use devices capable of scanning crowds for radiological devices and metal weapons outside the theater.
A permit for an antiwar demonstration has been issued for Orange Drive south of Sunset Boulevard, a few blocks from the ceremony. The permit allows up to 2,000 protesters, although LAPD officials said they are preparing for a much larger crowd.
Some precautions have been in place since the beginning of the month with street closures and restricted pedestrian access escalating up to Sunday. At midnight Saturday, the Hollywood Metro Station will be closed. The Metro line runs underneath the Hollywood & Highland complex, where the theater is located.
As of Monday night, Hollywood Boulevard between Orange Drive and Highland Avenue was closed to all traffic except city buses.
Even travelers outside the immediate area may face scrutiny and inconveniences. On the Hollywood Freeway, the California Highway Patrol plans to pay close attention to trucks and other large vehicles. CHP officers will order any vehicle stopping on the freeway to move on immediately or be removed.
All vehicles entering the area surrounding the theater will be searched by LAPD officers using mirrors to view their undercarriages as well as devices to detect explosives.
Bomb-sniffing dogs will be on duty. Anyone driving to or near the event is being warned to clean out vehicles to allow quick searches.