UnitedHealth Group shares tumbled Friday on a report that the U.S. Department of Justice has started an investigation into the health care giant’s Medicare billing practices.

The Wall Street Journal said federal officials have launched a civil fraud investigation into how the company records diagnoses that lead to extra payments for its Medicare Advantage, or MA, plans. Those are privately run versions of the government’s Medicare coverage program mostly for people ages 65 and over.

The paper, citing anonymous sources, said the probe focused on billing practices in recent months.

UnitedHealth said it wasn’t aware of the start of any new activity as the paper reported. It criticized the Journal’s report and said in a statement posted on its website, “Any suggestion that our practices are fraudulent is outrageous and false.”

The company’s UnitedHealthcare business covers more than 7.8 million people as the nation’s largest provider of Medicare Advantage plans. The business has been under pressure in recent quarters due to rising care use and rate cuts.

The Journal’s report “adds to a growing worry that expanded oversight around the insurers, particularly in the MA program, could pressure business practices, earnings, and investor sentiment,” Leerink Partners analyst Whit Mayo said in a research note.

Shares of the Minnetonka, Minnesota, company fell more than 6% Friday. Shares of other prominent Medicare Advantage insurers like Humana slipped while broader indexes also fell.

Hooters chain weighs bankruptcy

Hooters of America is working with creditors on a plan to restructure the business through bankruptcy court in the coming months, according to people with knowledge of the arrangements.

The casual dining chain is working with law firm Ropes & Gray to ready a filing, said the people, who added the plans are not final and asked not to be identified discussing private preparations. The court process would likely begin within the next two months, the people said.

The company has seven locations in California, according to its website.

The company, known for its skimpy server uniforms and double-entendre owl mascot, was working to address its debt load with its lawyers as well as turnaround advisers from boutique firm Accordion Partners, Bloomberg previously reported.

375,000 Teslas recalled over steering issue

Tesla is recalling more than 375,000 vehicles due to a power steering issue.

The recall is for certain 2023 Model 3 and Model Y vehicles operating software prior to 2023.38.4, according to the National Highway Traffic Safety Administration.

The printed circuit board for the electronic power steering assist may become overstressed, causing a loss of power steering assist when the vehicle reaches a stop and then accelerates again, the agency said.

The loss of power could require more effort to control the car by drivers, particularly at low speeds, increasing the risk of a crash.

Tesla isn’t aware of any crashes, injuries, or deaths related to the condition.

The electric vehicle maker headed by Elon Musk has released a free software update to address the issue.

Letters are expected to be sent to vehicle owners on March 25.

Owners may contact Tesla customer service at 1-877-798-3752 or the NHTSA at 1-888-327-4236.

Compiled from Bloomberg and Associated Press reports.