FEDERAL BUREAU OF INVESTIGATION agents, at least one of whom works on counterterrorism, went to the home of a former member of a climate activism group for questioning last week, potentially signaling a new escalation in the Trump administration’s promise to criminalize nonprofits and activist groups as domestic terrorists.

Two FBI agents, one from New York’s Joint Terrorism Task Force, told a former member of Extinction Rebellion NYC they wanted to ask him about the group at his home upstate on Friday, an attorney for the group told The Intercept. The visit followed a prior attempt to reach him at his old address.

The FBI’s apparent probe of Extinction Rebellion NYC comes as the Justice Department ramps up its surveillance of activists protesting immigration enforcement and the Trump administration creates secret lists of domestic enemies under Trump’s National Security Presidential Memorandum 7, or NSPM-7.

“I believe this to be a significant escalation of the criminal legal system against XR and find it very troubling,” said Ron Kuby, the Extinction Rebellion attorney. “This is usually the way we find out an actual investigation is underway and is often followed by other visits and other actions.”