By David Shepardson

(Reuters) - Utah sued Chinese-owned app TikTok on Tuesday, accusing it of harming children by intentionally keeping young users spending unhealthy amounts of time on the short-video sharing platform.

The Utah suit is the latest action challenging the popular app in the United States, with Indiana and Arkansas bringing similar suits.

Last month, a federal judge blocked California from enforcing a law meant to protect children when they use the Internet.

"What these children (and their parents) do not know

is that TikTok is lying to them about the safety of its app and exploiting them into checking and watching the app compulsively, no matter the terrible effects it has on their mental health, their physical development, their family, and their social life," said Utah Attorney General Sean Reyes in a filing.

Utah's suit filed in state court said the videos leverage "highly powerful algorithms and manipulative design features -- many of which mimic features of slot machines" and the result "of these manipulative tactics is that young consumers become hooked."

ByteDance-owned TikTok, which has more than 150 million U.S. users, said in response to the suit it "has industry-leading safeguards for young people, including an automatic 60-minute time limit for users under 18 and parental controls for teen accounts."

Reyes said the state's investigation is ongoing and he will ask a court next week to compel TikTok's compliance with investigative subpoenas.

Utah is seeking civil penalties as well as an injunction prohibiting TikTok from violating state law that protects consumers from deceptive business practices.

Indiana's lawsuit against TikTok, brought in December, is pending in state court.

Arkansas also sued both TikTok and Facebook-parent Meta (NASDAQ:META) in March "for pushing addictive platforms."

Last year, a group of Republican lawmakers said "many children are exposed to non-stop offerings of inappropriate content that TikTok’s algorithm force-feeds to them."

On Thursday, a judge will hear arguments in TikTok's lawsuit seeking to block Montana's first-of-its kind state ban on the use of TikTok before it takes effect Jan. 1. Montana's legislature approved legislation to ban TikTok citing spying concerns.

Congress has been considering legislation for months that would enable the Biden administration to restrict or ban TikTok over concerns of potential spying. TikTok has said it has spent more than $1.5 billion on rigorous data security efforts and rejects spying allegations.

Utah sues TikTok, claiming app has harmful impact on children 3