U.S. Senator Chris Murphy, D-Conn., tweeted that it was good Walmart decided to stop selling confederate flag merchandise, but that it should consider the same for certain gun types.

Murphy attached an image of the Sig Sauer M400 rifle that Walmart sells. It is described on the website as an AR platform tactical rifle that is designed for use in law enforcement, military operations, the sporting field and competitive shooting.

Murphy renewed his call that something be done to help curb massacres like the Charleston, S.C. shooting that left nine dead at a historic black church.

“The question for political leaders is whether we can live with ourselves if we continue our thundering silence in the face of these seemingly endless tragedies,” Murphy said in a statement after the shooting. “Whatever you think the answer is – changing firearms laws, fixing our mental health system, increasing resources for law enforcement – the time to act was long before today.”

Murphy has said one of his goals is to help pass comprehensive legislation to keep guns out of the hands of criminals, remove military-style weapons from streets and fix the country’s mental health system.

He has been a vocal advocate for more gun control after the Dec. 14, 2012 shooting at Sandy Hook Elementary School in Connecticut that left 20 children and six adults dead.