Private prison stocks fall after Elizabeth Warren says they should be banned

New York(CNN Business) Friday was a bad day for private prisons.

Democratic presidential candidate Elizabeth Warren is calling for private correctional and detention facilities to be banned. Shares of private prison operators dropped following her remarks.

Private prison operator CoreCivic's (CXW) stock was down 5%. Shares of The GEO Group (GEO), a Florida-based private prison and detention company, fell 5.6%. The broader stock market was flat to slightly higher on Friday.

Warren's campaign said it was unfazed by the stocks' slump.

"They shouldn't have a share price because they shouldn't exist," said Kristen Orthman, spokeswoman and director of communications for the Warren campaign.

A spokesperson for the Geo Group said its facilities are "highly rated by independent accreditation entities."

"Senator Warren's announcement is a continuation of politically-motivated attacks based on false narratives," the spokesperson said, adding the company would welcome lawmakers like Warren to come visit.

CoreCivic said "it's unfortunate that politicians advocate" against private prisons that "keep communities safe, enrolls thousands of inmates in reentry programs that prepare them for life after prison and saves taxpayers millions."

In a medium post, Warren said that as president she would end all contracts the federal government has with private prison operators. She also called the government out for working "hand-in-hand with private prison companies, who spend millions on lobbyists, campaign contributions, and revolving-door hires -- all to turn our criminal and immigration policies into ones that prioritize making them rich instead of keeping us safe."

Warren also called for criminal justice and immigration reform "to end mass incarceration and all of the unnecessary, cruel, and punitive forms of immigration detention that have taken root in the Trump administration."

If elected president, Warren pledged to create an independent oversight body within the Department of Justice to set and assess quality standards.