People arrive at the 2014 SXSW conference in Austin, Texas. Source: CNBC

The South by Southwest conference is facing a growing backlash after announcing plans to cancel two panels that looked to explore difference facets of the Gamergate movement.

Show organizers on Monday announced via a blog post that the two sessions — "SavePoint: A Discussion on the Gaming Community" and "Level Up: Overcoming Harassment in Games" — were being scrubbed after receiving "numerous threats of on-site violence related to this programming."

Among the topics to be explored by both sessions was the Gamergate movement — with one featuring supporters and the other detractors. The cancellations quickly became a trending topic on social media, with several people pointing out the irony of canceling a panel on harassment due to online harassment.

The fallout escalated Tuesday when BuzzFeed, which has had a significant presence at previous SXSW shows, threatened to withdraw from the 2016 festival if organizers did not reverse the decision.

"BuzzFeed has participated deeply in SXSW for years, and our staffers are scheduled to speak on or moderate a half-dozen panels at SXSW 2016," the site wrote in an open letter to Hugh Forrest, director of the SXSW Interactive Festival. "We will feel compelled to withdraw them if the conference can't find a way to do what those other targets of harassment do every day — to carry on important conversations in the face of harassment. We hope you can support the principle of free speech and engage a vital issue facing us and other constituents on the event."

The site stopped short of committing to the action, noting there were five months before the conference started, which it deemed adequate time to put appropriate security precautions in place.

Forrest, in a blog post Monday evening, defended the decision to cancel the sessions, saying it served the greater good of the festival.

"SXSW prides itself on being a big tent and a marketplace of diverse people and diverse ideas," he wrote. "However, preserving the sanctity of the big tent at SXSW Interactive necessitates that we keep the dialogue civil and respectful. If people can not agree, disagree and embrace new ways of thinking in a safe and secure place that is free of online and offline harassment, then this marketplace of ideas is inevitably compromised. ... Maintaining civil and respectful dialogue within the big tent is more important than any particular session."