A navy helicopter has already reached Renignuta airport near here and surveyed the fire, which is about three km from the famous Balaji temple atop Tirumala Hills.
Four IAF helicopters will reach Renigunta to join the operation at Seshachalam. Andhra Pradesh Governor E.S.L. Narasimhan, who is monitoring the situation, said C130 aircraft, which have expertise in chemical spraying to put off fire, will be pressed into service.
About 100 army personnel will join hundreds of civilian authorities battling the fire, which has already destroyed over 5,000 hectares of forest. Some navy personnel from Nellore district has already reached Tirumala.
Andhra Pradesh Chief Secretary P.K. Mohanty said the director general of forests and the director general of fire services will also be rushing to Tirumala from Delhi Thursday.
Mohanty spoke to the union cabinet secretary and secretaries of defence and forest and environment to brief them of the situation and seek help from the centre.
Tirumala Tirupati Devasthanam (TTD), which manages the affairs of the temple, has closed both the pedestrian pathways leading to Tirumala Hills as a precautionary measure. It has mobilized more than 1,000 personnel from forests, fire services, police and other departments to control the fire.
The authorities reportedly failed to take timely action, which resulted in the fire spreading to a vast area. A small fire was first spotted in the forest range a week ago. The forest department allegedly did not act on the alerts from the National Remote Sensing Centre (NRSC) and the National Aeronautics and Space Administration (NASA) of the US.
As Tirumala Hills is a no-fly zone, TTD had to consult the priests, before giving permission to deploy helicopters. This delay also led to the fire spreading to new areas.