The identity of NASA’s UFO research director will remain a secret to protect him from potential threats, agency officials said.

On Thursday morning, NASA published a report by a group of experts calling for a “government-wide approach” to collect data on UFOs, urging the public to use smartphone apps to help identify mysterious aerial craft.

Shortly after its release, NASA Administrator Bill Nelson told reporters that the agency had hired a research director for UAP — unidentified aerial phenomena, the government’s preferred term — who will oversee the space agency’s work on the topic and serve as a communicator between federal agencies on UFOs.

“They have been working there a while now, during the study, to help be a point of contact,” Nicola Fox, an associate administrator at NASA, told reporters.

When directly asked if she could name the official, Fox was blunt: “We will not give his name out.”

A main reason for the secrecy is that members of the independent study group received threats, Dan Evans, an assistant deputy associate administrator at NASA, told reporters.

Several members of the study were ridiculed on social media, received hate mail and said their colleagues were “warned” to stay away from researching such topics because it could damage their scientific credibility and potential for promotions, according to the report.

“That’s in part why we are not splashing the name of our new director out there, because science needs to be free,” Evans said. “Some of [the incidents] rose to actual threats.”

It’s unusual for a public official to remain anonymous, but NASA officials repeated that a major component of the study was to remove the stigma around those who want to report UFO sightings.

The research director is “tasked with developing and overseeing the implementation of NASA’s vision for UAP research,” Nelson said, with Fox adding that they “will serve as NASA’s point of contact for government entities.”