South by Southwest, the annual film, media and music festival held in Austin, Texas, canceled two panels on video gaming this week due to "threats of on-site violence." One of the panels, named "Level Up: Overcoming Harassment in Games," featured women who had previously been the targets of harassment for criticizing sexism in the video game industry.

Though South by Southwest, often called SXSW, did not release details of the threats it received, the festival is the latest host of discussions on the harassment of women in gaming that has been silenced by intimidation.

Last year, Utah State University's Center for Women and Gender received an email threatening a mass shooting if Anita Sarkeesian — a feminist media critic and creator of a series called "Tropes vs. Women in Video Games" — went through with a speaking engagement. Sarkeesian canceled. And game developers Brianna Wu and Zoe Quinn, vocal about sexism in gaming, both left their homes after receiving death threats, U.K. newspaper The Guardian reported.

In response to SXSW's decision to close the panels, Buzzfeed and Vox Media threatened to withdraw from the festival. Vox issued a statement saying, “By canceling the panels, they have cut off an opportunity to discuss a real and urgent problem in media and technology today.”

After the backlash, SXSW said that it was “considering an all-day event that focuses primarily on combatting online harassment,” the tech website Re/code reported. SXSW has since offered to reinstate the panel on harassment.

Even if SXSW reinstates the “Level Up” panel, it is unclear if the panelists will return.

“A big part of it is going to be security,” said Randi Harper, one of the scheduled panelists and founder of Online Abuse Prevention Initiative. “I’m not sure that they understand the security implications, and know that going forward they’re not going to make a mistake like this again.”

SXSW did not return a request for comment.

Panelists scheduled to participate in "Level Up" have received threats prior to their involvement in SXSW. Harper said she was laid off from her gaming industry job at KIXEYE Inc. due to an email smear campaign that claimed she was creating an industry blacklist (she noted, however, that KIXEYE told her she was laid off because of reorganization). Harper had created a tool to block Twitter harassment called Good Game Autoblocker.

In April, Harper said that she was “swatted.” Someone called in a threat to the police, and then gave her address, after which a SWAT team descended on her house. And another co-organizer of the “Level Up” panel, Caroline Sinders, wrote an account for Narrative.ly about a SWAT team that was sent to her mother’s house.

“Online harassment has become increasingly successful on silencing historically marginalized voices,” said Katherine Cross, a Ph.D. student at The City University of New York, and a gaming critic who had been scheduled to speak on the Level Up panel.

"I and many other Gamergate victims refuse to be defined by that," Cross said, referring to the online movement known for harassing women critical of sexism in the videogame industry. "Our panel was about the much wider issue of online harassment, and about developing productive solutions to the problem."