Washington (CNN) Sen. Mazie Hirono, a Democrat from Hawaii, said Friday that the FBI's supplemental investigation into Supreme Court nominee Brett Kavanaugh must cover what she called "the three credible" reports of misconduct.

"It certainly should cover the three credible reports that have come forward, and it has to be complete," Hirono told CNN's Wolf Blitzer on "The Situation Room."

"It has to be the kind of job that we expect the FBI to do -- and I believe that they can do it."

Hirono was referring to the accounts brought forward by Christine Blasey Ford, Deborah Ramirez and Julie Swetnick, who have leveled sexual assault or misconduct allegations against Kavanaugh stemming from his high school to his college years. Kavanaugh has vehemently denied all of the allegations.

Lawmakers opposing Kavanaugh's nomination have put their focus on these allegations rather than two additional accusations that became public this week. These include allegations of an assault made in anonymous letter and an account of a sexual assault a boat that was recanted by the accuser hours after it went public.

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