(Bloomberg) -- U.S. prosecutors are backtracking on a claim a Chinese woman brought a malware-infected thumb drive to President Donald Trump’s Mar-a-Lago resort in Florida.

The initial determination that the drive was infected may have been a “false positive,” Rolando Garcia, Assistant U.S. Attorney in West Palm Beach said Monday at a bail hearing for Yujing Zhang.

Zhang, who was formally indicted Friday, was detained March 30 for allegedly entering Mar-a-Lago without permission and lying to the Secret Service. At the time, she had four mobile phones, a laptop, an external hard drive and the thumb drive.

Zhang pleaded not guilty Monday, through her lawyer Kristy Militello.

To contact the reporter on this story: Jonathan Levin in Miami at jlevin20@bloomberg.net

To contact the editors responsible for this story: Michael J. Moore at mmoore55@bloomberg.net, Joe Schneider, Peter Jeffrey

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