Washington (CNN) The IRS is now sharing information with special counsel Robert Mueller about key Trump campaign officials, after the two entities clashed this summer over both the scope of the investigation into Russia's meddling in the 2016 election and a raid on former Trump campaign chairman Paul Manafort's home, people briefed on the matter tell CNN.

Part of the concern centered on the far-reaching and broad requests from Mueller's team. In the case of Manafort, Mueller's investigators are reaching back 11 years as they investigate possible tax and financial crimes, according to search warrant documents. Mueller is bound by a written order issued by Deputy Attorney General Rod Rosenstein in May which allows the special counsel to investigate "any matters that arose or may arise directly from the investigation."

After several months of being at odds, one source said, the IRS Criminal Investigation division is now sharing information about campaign associates, including Manafort and former White House national security adviser Michael Flynn. The sharing happened after the two camps reached an agreement following consultation with officials at the Treasury Department.

CNN has learned the IRS Criminal Investigation agents had been working with the FBI to investigate Manafort since before the election in a similar probe that centered on possible money laundering and tax fraud issues, according to the sources. It's unclear if Flynn is now or was previously under investigation by the IRS. CNN has reported that Mueller's team is examining Flynn's payments from Turkey and Russia

A former high-level Justice Department official says the information shared would include anything tax return-related such as real estate and banking records. The former official added the IRS is very restricted in what information it can share under Title 26 US Code and would normally need a specific grand jury subpoena in order to share tax returns with another agency.

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