The House Homeland Security Committee has called on the owner of 8chan, an unmonitored web forum frequented by white supremacists, to testify before the panel in light of the site’s connections to three mass shootings in the past year. Chairman Bennie G. Thompson (D-MS) and ranking member Rep. Mike Rogers (R-AL) sent a letter to owner Jim Watkins requesting his presence in front of the committee to answer for 8chan’s “efforts to investigate and mitigate the proliferation of extremist content, including white supremacist extremist content, on your website.” “Americans deserve to know what, if anything, you, as the owner and operator, are doing to address the proliferation of extremist content on 8chan,” reads the letter.

Watkins defended his forum in a video posted on YouTube Tuesday titled: “Sorry for the inconvenience, common sense will prevail.” The gunman who murdered 22 people in El Paso, Texas, on Saturday allegedly posted a racist manifesto on 8chan prior to the attack. Watkins claims that the gunman posted his manifesto on Instagram, and that it was later shared on 8chan by another user. The forum has also been linked to mass shootings in Christchurch, New Zealand, Pittsburgh, Pennsylvania, and Poway, California. 8chan is currently offline, as multiple internet service providers have dropped the site. Frederick Brennan—who first created 8chan in 2013 but no longer is associated with it—has called on the site to be shut down. “The only ones who will suffer from 8chan going down are mass shooters who planned to use it as a platform and Jim Watkins,” Brennan tweeted on Monday.