(CNN) An adviser to James Comey, Daniel Richman, on Wednesday night told CNN's Anderson Cooper that the FBI director was just doing his job in releasing information about emails discovered on Anthony Weiner's computer.

Richman's remarks on "AC360" came after President Obama warned earlier in the day against FBI "leaks" and "innuendo." They were the president's first public comments about the surprise announcement.

"It turned out that the investigation had to be continued because of the new trove of email," said Richman. "(The) fact that some new emails have been uncovered which the bureau has not, at least according to reporting, looked at it means that there is some new emails to look at. Nothing more."

Richman also declined to attack Obama -- suggesting the president's comments actually acted to dial back the controversy.

"The only difference ... is the president's wish that announcing completion meant completion," said Richman. "It just didn't happen to be true in this case."

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