NEW YORK (TheStreet) -- The U.S. Department of Justice and Federal Bureau of Investigation have opened a criminal investigation into multi-level supplements-seller Herbalife (HLF), The Financial Times reported late on Friday afternoon.

According to the FT's report, a criminal investigation may not lead to charges and will be led by the U.S. attorney and FBI's New York offices. The FT also said investigators have not charged Herbalife.

Friday's revelation hammered Herbalife shares and comes nearly a month after the company disclosed that the Federal Trade Commission opened a probe into its business practices. That probe was also first reported by the FT.

That move came over a year after hedge funder Bill Ackman of Pershing Square Capital Management took a $1 billion short position in Herbalife's shares and accused the company of being a pyramid scheme.

"We have no knowledge of any ongoing investigation by the DOJ or the FBI, and we have not received any formal nor informal request for information from either agency. We take our public disclosure obligations very seriously. Herbalife does not intend to make any additional comments regarding this matter unless and until there are material developments."

Herbalife shares tumbled nearly 14% in late Friday trading closing at $51.48. Shares have fallen over 20% in the past month, amid heightened regulatory scrutiny into the company's supplements business.

Since Bill Ackman made his short trade and accusations against Herbalife, hedge funders such as Dan Loeb of Third Point Management and Carl Icahn have taken opposing bets. Icahn has emerged as Herbalife's biggest supporter.

Amended Trade

After suffering large losses, Ackman amended his Herbalife trade so as to have synthetic short exposure to the company instead of a direct short. At an investor conference earlier this year, Ackman said his potential profit from the Herbalife short has grown. Around that time, Herbalife entered to a share repurchase agreement through a convertible note offering that Ackman said indicated the company might be struggling to obtain bank financing.

He also vowed to continue his fight against the company no matter the near-term performance and compared his trade to a short position in bond insurer MBIA (MBI) that eventually paid off.

Icahn's Board Seats

Billionaire activist Carl Icahn took the opposite of Ackman's trade. In 2013, Icahn cut a deal with Herbalife that gave him seats on Herbalife's board of directors and the right to buy up to 25% of the company's outstanding stock.

In March, Icahn took three additional seats on Herbalife's board amid departures by long-time directors. Icahn also confirmed he continues to hold his approximately 16% stake in Herbalife.

Icahn couldn't be immediately reached for comment on Friday.

Ackman Goes to Washington

Ackman and Herbalife both upped their lobbying efforts in 2013, as each party sought to make their respective arguments in Washington.

That comes as Ackman's losses forced the hedge funder to amend his short trade. He also conceded that succeeding or failing on his Herbalife short would ultimately come down to regulators in Washington. Ackman has lobbied hard to have both the FTC and the Securities and Exchange Commission investigate Herbalife.

Whether the FTC's review has been in the works for months, or was the result of Ackman's lobbying efforts is to be seen. A review of publicly disclosed political campaign donations indicates that Herbalife spent about 10 times the amount that Pershing Square did in Washington in 2013.

In January, Sen. Edward J. Markey (D., Mass.) asked that the SEC and FTC to seek more information into Herbalife's business practices. A day later, the League of United Latin American Citizens applauded Markey's probe.

In 2013, Pershing Square began lobbying in Washington, spending $90,000 with the Wexler & Walker Public Policy Association and $48,000 with the Moffett Group, a lobbyist that Politico reported worked to gain signatures on a letter Rep. Linda Sanchez (D-Calif.) sent to the FTC to investigate Herbalife's business practices. Pershing's lobbyists targeted signatures from the Congressional Hispanic Caucus (CHC), according to Politico's reporting. Prior to 2013, Pershing Square hadn't conducted lobbying in Washington.

Herbalife meanwhile spent $1.34 million on lobbying in 2013, according to OpenSecrets, including $950,000 from the company's lobbying group Herbalife International of America. The company also has spent lobbying money with Downey McGrath Group, Ogilvy Government Relations, the Podesta Group, Glover Park Group and International Business-Government Counsellors.

In addition to lobbying money, Herbalife's political action committee has generally increased its spending on elected officials. The PAC donated $61,478 to elected officials in 2011, $51,993 in 2012 and $106,600 in 2013.

-- Written by Antoine Gara in New York