The act of securing information about an enemy is called

The act of securing information about an enemy is called as reconnaissance.

Explanation:

Reconnaissance is a widely used technique in the military service. It is the activity of monitoring the opponent by visual and any other possible medium before attacking them.

It is a primary survey of the opponent and research to know everything about them. The main purpose of reconnaissance is to gather the information about the resources and available forces of the opponents or enemies.