A second House committee has asked online messaging platforms to walk lawmakers through their policies for detecting and reporting extremist content to authorities.

In the wake of conservative activist Charlie Kirk’s assassination on Sept. 10, House Homeland Security Chairman Andrew Garbarino (R-NY) and Subcommittee on Counterterrorism and Intelligence Chairman August Pfluger (R-TX) sent letters to Discord, GitHub, Reddit, and Twitch this week that asked the companies to explain how they are tracking and flagging concerning posts from users, the committee announced Tuesday.