WASHINGTON (NEXSTAR) — Big tech again came under fire on Capitol Hill Wednesday as lawmakers raised concerns about apps’ potential ties to the Chinese government.

National security officials are worried TikTok, a Chinese-owned social media video platform popular with kids, could give Beijing unfettered access to Americans’ data.

“TikTok just does not want to answer questions under oath,” Sen. Josh Hawley, R-Mo., said after representatives from TikTok refused to appear for a congressional hearing for a second time. “What they want to do is take all of this information from Americans, especially American teenagers, and then ship it off to Beijing.”

He called on all federal agencies to ban their employees from using the app, something the Department of Homeland Security, the Pentagon and the Department of State have already done.

“(TikTok) collects the sites that you visit, it collects your search history, it collects your keystrokes,” he listed during the Wednesday hearing.

“That should give us great concern,” said Bryan Ware, Homeland Security’s assistant secretary for cyber, infrastructure and resilience policy.

He, along with cybersecurity experts from the FBI and Department of Justice warned that sort of data could be weaponized.

“It creates a massive vulnerability of information that can be datamined,” Clyde Wallace, the deputy assistant director of the FBI’s Cyber Division, said.

“It makes it easier to target people,” Deputy Assistant Attorney General Adam Hickey explained. “It makes it easier for an intelligence service to either recruit or hack into systems used by a government employee.”

Hickey added that China’s not the only country to be worried about.

“Weeds are growing without, in my view, an international strategy,” Sen. Sheldon Whitehouse, D-R.I., said, saying the U.S. and its allies need to find ways to combat threats and warn users.

“Make the public know what the hazards are here,” he said.

Lawmakers are considering several bills to ramp up oversight and block companies from sending American data abroad.