The Southern Poverty Law Center said it's under criminal investigation over its use of paid informants to infiltrate extremist groups, blasting the move as yet another ploy by the Trump administration to target political foes.

SPLC interim CEO Bryan Fair said in a short, direct-to-camera video released Tuesday morning that the organization doesn't yet know all the details.

He described the investigation as an escalation of the pattern of hostility already shown to the SPLC during the second Trump administration, noting that FBI Director Kash Patel severed ties with the SPLC in October. Then in December, House Republicans "held a hearing to accuse us of being partisan and profitable," he said.

"For 55 years, the Southern Poverty Law Center has stood as a beacon of hope fighting white supremacy and various forms of injustice to create a multi-racial democracy where we can all live and thrive," Fair said in the video. "We are therefore unsurprised to be the latest organization targeted by this administration."

The U.S. Department of Justice did not respond immediately to a request for comment.

The SPLC is a nonprofit legal advocacy group that frequently litigates cases involving voting rights, prison reform and economic inequality. It's also known for its research into white supremacist and related extremist groups.

In Tuesday's video, Fair said the criminal investigation appears to center on the SPLC's previous use of paid informants to "gather credible intelligence on extremely violent groups."

Fair said that when the SPLC still used those methods, it always immediately turned over any relevant info to the FBI and local authorities.

He also said the use of informants was necessary in the SPLC's early years of the 1970s and 1980s, when the group repeatedly faced violent threats. In 1983, its offices in Montgomery, Alabama, were firebombed.

"There is no question that what we learned from informants saved lives," Fair said.

Fair said the SPLC no longer works with paid informants.

President Donald Trump has been repeatedly accused of using the powers of the federal government to target his political opponents during his second term. The DOJ has gone after law firms that previously opposed Trump, as well as individuals like former FBI Director James Comey, New York Attorney General Letitia James and former national security adviser John Bolton.

"Today, the federal government has been weaponized to dismantle the rights of our nation's most vulnerable people and any organization like ours that stands in the breach," Fair said in Tuesday's video.

"We will vigorously defend ourselves, our staff, and our work; we will continue to fight hate; and we will continue to seek a safer and more just world," he added.

--Editing by Nicole Bleier.