Conscious of threats posed by Pakistan-based terrorists to its bases, IAF chief NAK Browne today said the Air Force has taken all "necessary" steps to protect its assets and stations.

"It is a very valid concern. These kinds of things have happened in our neighbourhood (Pakistan) and in last two years, there have been three such incidents there. We are very conscious of those things and all necessary steps have taken to protect our assets.

"We are extremely vigilant," Browne told reporters at the air base here after the 81st IAF Day parade.