A 350-word entry in the Internal Revenue Manual instructed agents of the U.S. tax agency to omit any reference to tips supplied by the DEA's Special Operations Division, especially from affidavits, court proceedings or investigative files. The entry was published and posted online in 2005 and 2006, and was removed in early 2007. The IRS is among two dozen arms of the government working with the Special Operations Division, including the Federal Bureau of Investigation, the National Security Agency and the Central Intelligence Agency.

An IRS spokesman had no comment on the entry or on why it was removed from the manual. Reuters recovered the previous editions from the archives of the Westlaw legal database, which is owned by Thomson Reuters Corp, the parent of this news agency.

As Reuters reported Monday, the Special Operations Division of the DEA funnels information from overseas NSA intercepts, domestic wiretaps, informants and a large DEA database of telephone records to authorities nationwide to help them launch criminal investigations of Americans. The DEA phone database is distinct from a NSA database disclosed by former NSA contractor Edward Snowden.