WASHINGTON — Republican Iowa Sen. Chuck Grassley requested from the Justice Department and FBI Friday information about how an FBI translator was allegedly able to go to Syria and marry the ISIS operative who she was supposed to be investigating.

In a letter to Deputy Attorney General Rod Rosenstein and Acting FBI Director Andrew McCabe, Grassley asked for answers pertaining to how the romantic relationship came about and the FBI was unaware of it the entire time.

Grassley also requested any prior or newly implemented policies that dealt with situations like this — specifically about the vetting process for hiring contractors — as well as if there were any reviews or disciplinary actions taken because the incident.

“This rogue employee had access to highly sensitive national security information. I’m troubled that a relationship between an FBI employee and a prominent ISIS recruiter went unnoticed, and more troubled that there wasn’t a safeguard to successfully catch this incident,” Grassley said in his letter to Rosenstein and McCabe.

German national, Denis Cuspert, known by ISIS as Abu Talha al-Almani, entered into a romantic relationship with then-FBI translator Daniela Greene in 2014, CNN first reported, and married Greene despite her marriage to another man in the U.S.

The U.S. considers Cuspert to be a “specially designated global terrorist.” He escaped a U.S. missile strike in 2015 and is claimed to be living in the ISIS-controlled region of Syria.

The FBI assigned Greene to assist in investigating Cuspert and Greene found him by communicating through three Skype accounts. But CNN notes that the FBI was only aware of two of those accounts. She told the bureau she was traveling to Germany to visit family when, in fact, she took a series of flights to take her to Turkey and crossed the border into Syria with the help of Cuspert.

After realizing she made a mistake, she wrote emails to the U.S. saying: “I was weak,” and “I really made a mess of things this time.”

Another email from Greene the next day said: “I am gone and I can’t come back…. I am in Syria…. I am in a very harsh environment and I don’t know how long I will last here, but it doesn’t matter, it’s all a little too late.”

She added, “I will probably go to prison for a long time if I come back, but that is life.”

Greene departed Syria in August 2014, leaving ISIS and returned to U.S. soil. Authorities arrested her upon arrival.

“It’s important for the public to understand how this happened and how similar problems will be prevented in the future. We also need to know how prosecutors settled on the charges in this case. A sentence of two years seems unusually light for such a potential threat to national security,” Grassley said.

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