The makers and promoters of OxyElite Pro, the weight-loss supplement that is blamed for the deaths of two Hawaii residents, pleaded guilty to felony charges in Dallas.

Five people and two companies pleaded guilty to a scheme to “fraudulently sell” the popular supplements known as Jack3d and OxyElite Pro, distributed by Dallas-based USPlabs, the Department of Justice announced Friday.

Cyril Willson and Matthew Hebert said they introduced the supplements “with the intent to defraud or mislead,” while Jonathan Doyle, president of USPlabs, pleaded guilty to conspiracy to introduce “misbranded food into interstate commerce.”

Sitesh Patel, vice president of S.K. Laboratories, a California dietary supplement manufacturer, also pleaded guilty, along with Jacobo Geissler, CEO of USPlabs. The indictment said that the defendants conspired to import the dangerous supplement ingredients from China, including a synthetic stimulant, and lied about the source of the ingredients, claiming they contained natural plant extracts.

In October 2013, as the number of cases of liver damage and acute hepatitis linked to the consumption of OxyElite Pro began to climb in Hawaii, the state Health Department ordered Hawaii retailers to take OxyElite Pro products off their shelves. The DOH said it was investigating more than 40 cases involving people who had developed symptoms of acute liver inflammation, also known as nonviral hepatitis, after consuming the supplement. Two people underwent liver transplants, and two others died of liver failure.

The supplement was recalled in 2013 amid an investigation by the Food and Drug Administration, and the defendants were charged in a 2015 indictment by a federal grand jury in the Northern District of Texas.

Patel faces a maximum six years’ imprisonment; Doyle and Geissler face up to five years; and Willson and Hebert face up to three years. The defendants and companies agreed to pay roughly $60 million in criminal fines.