The chief executives of social media companies Meta, X, TikTok, Snap, and Discord faced tough questions on their efforts to combat online child sexual exploitation at a U.S. Senate hearing on Wednesday.

Senator Dick Durbin, the Judiciary Committee's Democratic chairman, cited statistics from the National Center for Missing and Exploited Children nonprofit group that showed financial "sextortion," in which a predator tricks a minor into sending explicit photos and videos, had skyrocketed last year.

"This disturbing growth in child sexual exploitation is driven by one thing: changes in technology," Durbin said during the hearing.

As the hearing kicked off on Wednesday, the committee played a video in which children spoke about being victimized on the social media platforms.

"I was sexually exploited on Facebook," said one child in the video, who appeared in shadow.

In the hearing room, dozens of parents stood waiting for the CEOs to enter, holding pictures of their children.

"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," said Senator Lindsey Graham, referring to Meta CEO Mark Zuckerberg. "You have a product that's killing people."

Wednesday also marks the first appearance by TikTok CEO Shou Zi Chew before U.S. lawmakers since March when the Chinese-owned short video app company faced harsh questions, including some suggesting the app was damaging children's mental health.

"We make careful product design choices to help make our app inhospitable to those seeking to harm teens," Chew said, adding TikTok's community guidelines strictly prohibit anything that puts "teenagers at risk of exploitation or other harm -- and we vigorously enforce them."

Chew disclosed more than 170 million Americans used TikTok monthly -- 20 million more than the company said last year.

Under questioning by Graham, he said TikTok would spend more than $2 billion on trust and safety efforts, but declined to say how the figure compared to the company's overall revenue.

Zuckerberg, whose Meta owns Facebook and Instagram; X CEO Linda Yaccarino; Snap CEO Evan Spiegel; and Discord CEO Jason Citron also testified.

"We’re committed to protecting young people from abuse on our services, but this is an ongoing challenge," Zuckerberg said in testimony delivered at the hearing. "As we improve defenses in one area, criminals shift their tactics, and we have to come up with new responses."

Zuckerberg reiterated that the company has no plans to move forward with a previous idea to create a kids version of Instagram.

Speigel said Snap's parental controls resemble "how we believe parents monitor their teens activity in the real world – where parents want to know who their teens are spending time with but don’t need to listen in on every private conversation."

The committee last year approved several bills, including one that would remove tech firms' immunity from civil and criminal liability under child sexual abuse material laws that was first proposed in 2020. None have become law.

Senator Amy Klobuchar on Wednesday questioned what she said was inaction in the tech industry, comparing it to the response shown when a panel blew out of a Boeing plane earlier this month.

"When a Boeing plane lost a door in flight several weeks ago, nobody questioned the decision to ground a fleet. ... So why aren't we taking the same type of decisive action on the danger of these platforms when we know these kids are dying?" Klobuchar said.