Six more U.S. senators on Friday backed bipartisan legislation to give President Joe Biden new powers to ban Chinese-owned video app TikTok on national security grounds as the Chinese company ramped up efforts to get its story heard in Washington before an important hearing next week.

Earlier this month, 12 senators led by Democrat Mark Warner and Republican John Thune unveiled legislation backed by the White House to give the Commerce Department new powers to address TikTok that has more than 100 million US users.

The announcement comes after TikTok said this week the Biden administration demand its Chinese owners divest their stake in the company or it could face a potential US ban.

Biden’s predecessor, Republican Donald Trump, had tried to ban TikTok in 2020 but was blocked by US courts.

The legislation, the Restricting the Emergence of Security Threats that Risk Information and Communications Technology (RESTRICT) Act, now has nine Republicans and nine Democratic sponsors to address fears ByteDance-owned TikTok’s US user data could be passed on to China’s government.

Separately, a source confirmed to Reuters Friday the Justice Department has opened a criminal investigation after ByteDance said in December some employees improperly accessed US TikTok user data of two journalists.

Reuters reported in December four ByteDance employees who were involved in the incident were fired, including two in China and two in the United States. Company officials said they were taking additional steps to protect user data.

ByteDance employees accessed the data as part of an unsuccessful effort to investigate leaks of company information earlier this year, and were aiming to identify potential connections between two journalists.

TikTok’s chief executive officer Shou Zi Chew will appear the first time before Congress when he testifies before the House Energy and Commerce Committee on March 23.

TikTok said content creators will come to Washington next week to make the case why the app should not be banned. “Lawmakers in Washington debating TikTok should hear firsthand from people whose lives would be directly affected by their decisions,” TikTok said Friday.

By David Shepardson and Echo Wang; Editor: Diane Craft

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