A group of former FBI agents filed a lawsuit on Monday claiming they were unlawfully fired for kneeling during a 2020 racial justice protest in the US capital.

A five-year-old photo of agents kneeling at a D.C. protest after George Floyd’s killing led to the firing of about 16 agents.

The suit involves one of the largest groups of former law enforcement officials to challenge the Trump administration in court over its continuing purge of personnel.