Story highlights Former national security adviser Michael Flynn has provided some documents to Congress

Flynn's lawyers and the Senate intel committee agreed on a schedule to provide documents

(CNN) The leaders of the Senate Russia investigation are probing for more information from former national security adviser Michael Flynn, a process that is ongoing as he provides additional documents in response to their subpoenas.

"We continue to work through documents that are supplied to us and we are making a lot of progress," Senate intelligence committee Chairman Richard Burr said Tuesday.

Sen. Mark Warner, the top Democrat on the investigation, said they planned to discuss more what they were looking for in the second batch of documents they are seeking from Flynn.

"Where there were gaps, we still haven't gotten that full (production) from them," Warner said.

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