Samuel Lerma, Arzetta Hodges and Desiree Qunitana join mourners at a vigil at El Paso High School after a mass shooting at a Walmart store in El Paso, Texas, Aug. 3, 2019.
Samuel Lerma, Arzetta Hodges and Desiree Qunitana join mourners at a vigil at El Paso High School after a mass shooting at a Walmart store in El Paso, Texas, Aug. 3, 2019.

LOS ANGELES - As Americans reflect on two mass shootings that claimed 31 lives last weekend, they’re asking how to stop the carnage.

Researchers at a Los Angeles center devoted to tolerance say part of the answer lies in ending hate online. Political leaders and social media companies, they add, must help to tone down the hateful rhetoric.

Rick Eaton, senior researcher at the Simon Wiesenthal Center, a Jewish human rights organization, studies online hate. He points to an internet game that encourages players to shoot people crossing the border. Another site created with the popular gaming site Minecraft shows an animated crematorium for Jews. On a third blogging site called Gab, some users applaud hate crimes.

WATCH: Researchers Call for Action to Stem Online Hate

Targets of the vitriol include African Americans, Jews and Muslims, but the groups are variable, Eaton said.

“If it’s immigrants in Texas, as it was this past weekend, (or) if it’s another community, such as the Somali community up in the Upper Midwest, they’ve always been flexible,” he said.

In recent years, Eaton said much of the online hatred has focused on immigrants.

FILE - A person pauses in front of Stars of David with the names of those killed in a deadly shooting at the Tree of Life Synagogue in Pittsburgh, Oct. 29, 2018.

Victims of intolerance

The center’s Museum of Tolerance, which tells the story of the Holocaust and other genocides, highlights the faces of victims of atrocities, including survivors of shootings at a Sikh temple and a Jewish school.

Mass killers today are often inspired by and communicate on social media sites, including the gunman who killed 11 people at a Pittsburgh synagogue last year, and the perpetrator in the El Paso killings.

“The shooter in El Paso posted a manifesto online consumed by racist hate,” noted President Donald Trump on Monday. The manifesto appeared on 8Chan, a site that extremists posted to in three recent mass shootings. Technical providers have stopped support for the site.

Trump condemned white supremacy in remarks after the weekend shootings, calling for stronger background checks for prospective gun owners and reforms in mental health law. He did not call, critics noted, for sweeping gun restrictions, although he said Sunday that perhaps more is needed on gun control.

Trump also condemned “racist hate.”

President Donald Trump speaks to members of the media on the South Lawn of the White House in Washington, Aug. 7, 2019.

“His speech, in terms of denouncing white supremacy, was extremely welcome,” said Rabbi Abraham Cooper, the Wiesenthal Center’s associate dean. “Will he be more thoughtful on his tweets?” he asked.

Democrats have criticized Trump’s statements on Twitter concerning minority members of Congress, including Alexandria Ocasio-Cortez and three of her colleagues who are also women of color.

Setting the tone

The Wiesenthal Center’s founder and dean, Rabbi Marvin Hier, offered a prayer at Trump’s inauguration in January 2017, and the center has the ear of many in Washington. Cooper says both Trump and leading Democrats must set the tone.

“We’re about to go into the presidential (election) season again with, I would say, an almost hysteric level of demonization of the other,” he said. “We need a cease-fire.”

Cooper said more action is also needed from social media companies, which researchers at the Wiesenthal Center grade annually on their efforts against hate speech. The lowest grade for a major media site went to, which is based in Russia.

He said online sites provide a sense of validation for lone wolves — isolated individuals who engage in acts of violence.

“What social media has provided for the lone wolf is a sense of community, a sense of empowerment, because there are other people out there cheering you on,” he said.

Cooper argues that social media companies must do more or face demands for government regulation, which he said few would welcome.

He pointed to a letter on display at the Wiesenthal Center, signed by a young Adolf Hitler, which he said shows what can happen when hatred is unchecked and goes viral. That occurred, he noted, in the age of typewriters, before the internet and social media.