The House Intelligence Committee’s Democratic chairman and Republican ranking member are threatening to hit the Justice Department with a rare bipartisan subpoena if the department doesn’t hand over testimony and briefing materials produced by Special Counsel Robert Mueller during the Russia investigation.

In a letter dated April 25, Chairman Adam Schiff (D-CA) and Ranking Member Devin Nunes (R-CA) wrote to Attorney General Bill Barr, Deputy Attorney General Rod Rosenstein, and FBI Director Christopher Wray to complain that the “Department of Justice and the FBI failed to keep the Committee ‘fully and currently informed’” of foreign intelligence and counterintelligence information obtained in the course of Mueller’s investigation. Schiff and Nunes expressed concerns that the Department and Bureau also failed to the address the committee’s prior request for Mueller to testify before the committee.

“In addition to the complete unredacted report, the Committee’s request includes all classified and unclassified evidence and information obtained or generated by the Special Counsel’s Office that may relate to foreign intelligence or counterintelligence matters,” the letter states.

The request also includes information regarding “efforts by the Russian government to contact Americans in furtherance of Russian intelligence objectives,” and says it is “unique and distinct from the House Judiciary Committee’s independent interest in obtaining the unredacted report and underlying evidence.”

Schiff and Nunes set a May 2 deadline, warning that “the Committee will have no choice but to resort to compulsory process on Friday, May 3 to compel production of documents responsive to the Committee’s request” if the deadline is not met.

Reached by phone on Tuesday, Rep. Ro Khanna (D-CA) told The Daily Beast that the committee has now started to proceed through the compulsory part of the process. “The extraordinary thing is that it’s bipartisan,” Khanna said.

Rep. Eric Swalwell (D-CA) told The Daily Beast the House committee’s letter was necessary because “we need to know if there’s an ongoing threat to our national security.”

“The Mueller Report found 200 pages of contacts between Donald Trump’s campaign and the Russians. But not once did it say these disturbing contacts ceased,” he said.