During a peaceful protest against police violence on Thursday night, a sniper opened fire and fatally shot five officers, authorities confirmed.

Twelve other officers and two civilians were also injured in the shooting.

The protest was held in response to recent police shooting deaths of two African-American men—Alton Sterling in Baton Rouge, Louisiana, and Philando Castile in Falcon Heights, Minnesota.

Some local celebrities and politicians took to social media to respond to the news.