Temple sources told PTI today that the entire Tirumala including the pilgrim vehicular routes and stairways leading to the hill shrine was put on high security alert.
Special bomb squads have also been pressed into service and they were on the job to scan all vulnerable spots on the hills, they said.
Already surveillance cameras were erected to watch the movements of pilgrims and others at several places including the temple complex and massive queue complexes on the hills, they said.