Republican House intelligence committee chairman Devin Nunes says his committee is investigating the Obama administration State Department. Meanwhile, Senate investigators are using these officials as sources in its probe into Russian election interference—pointing to the massive differences between the two probes.

Multiple sources familiar with the Senate intelligence committee’s investigation tell The Daily Beast that Republican and Democratic staffers there have spoken with numerous people who worked in the State Department under then-Secretary of State John Kerry.

Tom Malinowski, who was Kerry’s assistant secretary of state for Democracy, Human Rights, and Labor, told The Daily Beast that he spoke with Senate investigators. He said the meeting was informational and conversational, but didn’t elaborate.

Committee staff have also spoken with Jon Finer, Kerry’s chief of staff at State, according to a person familiar with that conversation. Both Democratic and Republican staff attended.

Staffers spoke as well with Victoria Nuland, assistant secretary for European and Eurasian affairs, according to another source. Nuland is a favorite target of Russian state media, which leaked her phone calls in 2014. And Carter Page, the Trump campaign adviser-turned-FBI counterintelligence surveillance target, blamed her for “fomenting” efforts that ousted former Ukrainian President Viktor Yanukovych. Yanukovych, incidentally, was one of Paul Manafort’s many controversial clients.

It isn’t surprising that Trump/Russia investigators would chat with former Foggy Bottom officials. The department’s diplomats have long tracked the Kremlin’s efforts to expand its regional hegemony—often using violent and illicit means. Malinowski, Nuland, and Finer all worked at high levels in the State Department while the Kremlin’s meddling efforts were underway.

Nunes, meanwhile, has promised to release information about the State Department’s potential role in the distribution of the Steele dossier.

“We are in the middle of like whole phase two of our investigation, which involves other departments, specifically the State Department and some of the involvement that they had in this,” Nunes told Fox News in his first interview after the release of his controversial memo on surveillance of Page. “That investigation is ongoing and we continue to work towards finding answers and asking the right questions to try to get to the bottom of what exactly the State Department was up to in terms of this Russian investigation.”