Sen. Josh Hawley, R-Mo., called on Meta's Zuckerberg to directly apologize to the families in the room.
The chief executives of the nation's top social media companies were grilled on Capitol Hill Wednesday over child safety, with lawmakers accusing the tech leaders of failing to protect kids from exploitation and abuse.
"Mr. Zuckerberg, you and the companies before us -- I know you don't mean it to be so, but you have blood on your hands," Sen. Lindsey Graham, R-S.C., said in his opening remarks. The comment prompted applause from families gathered in the hearing room whose children died after being ensnared in some of the darker sides of their platform.
"You have a product that's killing people," Graham added.
Later on in the hearing, Sen. Josh Hawley, R-Mo., called on Meta's Zuckerberg to directly apologize to the families in the room.
"They're here. You're on national television ... Would you like to apologize for what you've done to these good people?" Hawley pressed.
The CEO of Meta, the parent company of both Facebook and Instagram, then stood up and turned around to address parents.
"It's terrible. No one should have to go through the things that your families have suffered," Zuckerberg told them. "And this is why we invest so much and are going to continue doing industry-leading efforts to make sure that no one has to go through the things your families have had to suffer."
The Senate Judiciary Committee, in a hearing intended to drum up support for federal legislation to safeguard children from the online world, is also hearing from X's Linda Yaccarino, TikTok's Shou Chew, Snap's Evan Spiegel and Discord's Jason Citron.
Sexual exploitation of children online is a growing problem in the U.S. According to the National Center for Missing & Exploited Children, daily cyber tips of child sexual abuse material online have gone up tenfold in the past 10 years, reaching 100,000 daily reports in 2023.
Chairman Dick Durbin, D-Ill., called online child exploitation a "crisis in America" fueled by rapid changes in technology that give predators "powerful new tools" to target kids.
Of the CEOs testifying, Durbin said "they are not only the tech companies that have contributed to this crisis, they are responsible for many of the dangers our children face online."
"Their design choices, their failures to adequately invest in trust and safety and their constant pursuit of engagement and profit over basic safety have all put our kids and grandkids at risk," he said in his opening statement.
Graham acknowledged there were some positives to the social sites, but "the dark side hasn't been dealt with."
"It's now time to deal with the dark side because people have taken your idea and they have turned it into a nightmare for the American people," Graham said.
In response, the CEOs largely leaned into highlighting actions they've taken to try to alleviate these problems. Meta recently announced plans to hide content it deems inappropriate for teens, and Zuckerberg highlighted the 30 tools they've built to protect kids and help parents navigate the online world.
Each of the CEOs addressed the families in the room and gave their condolences, though Zuckerberg also pushed back on the link between mental health and social media in his opening remarks.
"With so much of our lives spent on mobile devices and social media, it's important to look into the effects on teen mental health and well being. I take this very seriously," Zuckerberg said. "Mental health is a complex issue and the existing body of scientific work has not shown a causal link between using social media and young people having worse mental health outcomes."
Wednesday marks the first time Snap's CEO, Spiegel, is providing testimony on Capitol Hill in response to allegations that Snapchat is harming children's mental and physical health.
Snapchat is also being sued in a class action lawsuit by several parents in California, many of whom say they lost their child to fentanyl poisoning and overdose with pills bought on Snapchat.
Spiegel said he feels "profound sorrow" that his service has been "abused to cause harm."
Spiegel also discussed his support for The Kids Online Safety Act during Wednesday's hearing. The "KOSA" bill aims to remove "harmful ads and posts, such as addiction, eating disorders, and suicide from showing up on children's accounts," according to supporters of the bill.
"I want to encourage broader industry support for legislation protecting children online," Spiegel said. "No legislation is perfect, but some rules of the road are better than none."
Yaccarino said X was supportive of KOSA, but Chew, Citron and Zuckerberg didn't commit to backing the bill in its current form.
Legislative efforts at the national level have mostly failed, but state legislators have introduced more than 100 bills that aim to regulate how children interact with social media.
Durbin noted the failure to push federal legislation forward, saying "the tech industry alone is not to blame for the situation we're in, those of us in Congress need to look in the mirror."
Graham, the ranking member of the committee, said Republicans are "ready to answer the call."
"These companies must be reigned in, or the worst is yet to come," Graham said.
But the CEOs largely showed no consensus of support for the various bills being pushed by lawmakers.
Snap's Spiegel was the only CEO to support KOSA. X's Yaccarino said she supported the SHIELD Act, which would allow criminal prosecution of people who share others' private images online without consent, and the Stop CSAM Act, a bill to crack down on the proliferation of child sex abuse material. Asked if he supported the measure, Chew said the spirit of the bill is "in line with what we want to do" and would comply if it became law.
Zuckerberg, Meta's CEO, said he agrees with the "goals" in some of the handful of bills, but not the specifics -- and redirected to Meta's own legislative proposal.
Sen. Sheldon Whitehouse, D-R.I., said he wanted each CEO to put in writing what reforms they'd support to Section 230 -- a 1990s law that has given sweeping legal immunity to tech and social media companies.
ABC News' Becky Worley and Tenzin Shakya contributed to this report.