Federal authorities say dozens of people associated with white-supremacist gangs in Texas have been indicted on drug trafficking charges, including four accused in a kidnapping in which a hatchet was used to chop off a victim's finger.

Authorities said Monday that 57 people are charged. Forty-two were arrested last week, nine people were already in custody on unrelated charges and six are still being sought.

An indictment alleges the defendants were members of the Aryan Brotherhood of Texas and other gangs. Prosecutors allege the scheme began in 2015, as members conspired to distribute methamphetamine in Texas.

Prosecutors say four defendants early this year kidnapped someone in an effort to obtain drug proceeds they believed were owed to them. Investigators say the victim was beaten and had a finger lopped off.