A Violent Protest is a Powerplay-related System Signal Source specific to Pranav Antal. It is similar to a Conflict Zone, but contains ships aligned to a Power battling against a system's defense forces. At these sites, the Power is trying to prepare the system for its expansion there by provoking civil unrest against system security. When aligned to Pranav Antal, pilots will receive 10 Powerplay (bonds) per ship killed at Violent Protests.
To locate a system with active Violent Protests, check the "Expansion" tab of Pranav Antal in the Galactic Powers menu.