A group of irate U.S. Senators want to know exactly when the Department of Justice plans to complete its probe into the death of late pedophile Jeffrey Epstein.

Senators Ben Sasse (R-NE), Richard Blumenthal (D-Connecticut), Ted Cruz (R-Texas), and Marsha Blackburn (R-Tennessee) asked DOJ Inspector General Michael Horowitz in a letter Monday why there were still no answers almost four months after the 66-year-old was found dead in his cell in the Metropolitan Detention Center.

“Epstein’s death in federal custody represents a colossal failure by the Department of Justice,” the letter reads. “As the kingpin of a child sex trafficking ring, Epstein possessed unique insight into the crimes of his friends and associates. That knowledge died with him, making it significantly harder to prosecute his co-conspirators. These wealthy and powerful men raped innocent children, and it is an outrage that the Department’s inability to keep Epstein alive — after a previous apparent suicide attempt — makes it less likely that these monsters can be brought to justice.”

The note requests that Horowitz brief the bi-partisan group by the end of the week, as well as lay out a timeline for the conclusion of the IG’s investigation.

While Epstein’s death was officially ruled a suicide by hanging, a forensic pathologist hired by his brother claims the financier’s injuries were more consistent with homicidal strangulation.

Last month, federal prosecutors charged corrections officers Tova Noel and Michael Thomas with falsifying documents claiming they’d checked on Epstein and other inmates every half hour the night he died. Both guards pleaded “not guilty.”

No other charges have been filed, or reports publicly released, in connection with the investigation, though Attorney General William Barr has referred to the death as “a perfect storm of screw ups.”

The DOJ did not immediately return a message.