Two top House Republicans on Wednesday sent a letter to the Justice Department inspector general, urging the agency watchdog to investigate leaks about communications between aides to President Donald Trump and Russian officials.

“We have serious concerns about the potential inadequate protection of classified information here,” wrote Rep. Jason Chaffetz (R-UT), chair of the Oversight Committee, and Rep. Bob Goodlatte (R-VA), chair of the Judiciary Committee. “In light of this, we request that your office begin an immediate investigation into whether classified information was mishandled here.”

In the letter, the two chairmen cited news reports about former National Security Adviser Michael Flynn’s communications with the Russian ambassador. Those reports said that Flynn’s conversations were discovered when U.S. officials intercepted communications. Reports that additional Trump aides spoke with Russian officials ahead of the election also said that U.S. officials discovered the conversations by intercepting the communications.

“Generally, collection activities by intelligence agencies are classified,” Chaffetz and Goodlatte wrote in their letter, adding later that the “release of classified national security information can, by definition, have grave effects on national security.”

In the wake of Flynn’s resignation, Trump and several House Republicans have focused on the leaks that led to the revelations about his communications with the Russian ambassador. However, some Republicans have said that while investigating the leaks is important, the focus of Congressional probes should be about the Trump administration’s relationship with Russia.

Read the letter: