Two U.S. senators are calling for an outside investigation into how the Air Force Academy handles sexual assaults, including an allegation that agents were blocked from speaking to academy football coaches.

Sen. Kirsten Gillibrand (KEER'-sten JIHL'-uh-brand) of New York and Sen. John Thune (thoon) of South Dakota asked the Defense Department and civilian investigators on Wednesday to investigate allegations by a former Air Force agent.

The former agent, Staff Sgt. Brandon Enos, said former academy Superintendent Michael Gould wouldn't let investigators talk to football coaches about allegations of sexual assault and drug use. Enos says Gould spoke to the coaches himself and concluded there was no wrongdoing.

Gould denied doing anything improper. He's now retired.

The Colorado-based academy says multiple agencies have concluded the school handles sexual assault cases appropriately.

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