Agents with the Department of Homeland Security’s inspector general’s office interrupted a CBS News interview with a former ICE spokesperson and whistleblower Wednesday.

James Schwab, who was a spokesperson for Immigration and Customs Enforcement until March, was speaking to CBS News’ Jamie Yuccas when two DHS agents appeared at his door.

Schwab later said he was “very surprised” by the visit, and that he believed it was “absolutely” an attempt to intimidate him. The interview footage aired Thursday morning.

Schwab left the agency after, he said, he was asked to perpetuate a lie on Attorney General Jeff Sessions’ behalf regarding Libby Schaaf, the mayor of Oakland. The day before an ICE raid in Oakland earlier this year, Schaaf spoke about it publicly, warning residents to take care.

Afterward, acting ICE Director Thomas Homan accused Schaaf of preventing 800 arrests with her warning. Sessions repeated the that number, which Schwab said is not accurate, in a speech later.

When asked by reporters about Sessions’ claim, Schwab said he was instructed to refer them to a previous statement he’d made about Schaaf, without correcting Sessions’ error. That’s when he quit, he said.

“They just said that they wanted to talk to me about the leak with the Oakland mayor,” Schwab told Yuccas after the agents left on Wednesday. He said he’d never communicated with Schaaf.

Watch CBS News’ interview, including the interruption by DHS agents, below: