By Tom LoBianco and Manu Raju

CNN

(CNN) -- Members of the House oversight committee are set to review the first batch of documents in response to their probe into whether President Donald Trump's former national security adviser, Michael Flynn, properly disclosed payments from foreign governments on his security clearance application.

The committee is gathering Tuesday morning at the Capitol to review classified material provided by the Department of Defense in response to its March 22 request for more information on Flynn, according to MJ Henshaw, a spokeswoman for House Oversight Chairman Jason Chaffetz.

The committee has sent additional requests for information about Flynn to the White House, the FBI and the Office of the Director of National Intelligence. However, Tuesday's meeting will only include responses from the Pentagon.

Oversight investigators revealed last month that Flynn had received more than $45,000 for a speech he gave to RT-TV in Russia and $530,000 for work his lobbying firm did that, according to the committee, likely benefited the Republic of Turkey.

The House and Senate intelligence committees have been leading the primary investigations into Russia's interference in the US elections and possible coordination with top aides to the Trump campaign. However, the House oversight panel has taken a particular focus on Flynn's work -- drilling down in a series of requests.

Flynn was forced to resign from his role as Trump's national security adviser after it was discovered he withheld information about discussions he had with Russian ambassador to the US Sergey Kislyak. Flynn is one of four former Trump aides at the center of the FBI's probe and is a top target for House and Senate investigators as well.

Since he resigned, Flynn has retained a lawyer and has offered to testify in exchange for immunity from prosecution -- an offer nobody has apparently taken him up on.