Federal prosecutors on Monday backtracked on their claim that a Chinese woman brought a malware-infected thumb drive to President Donald Trump’s Mar-a-Lago resort in Florida last month. Yujing Zhang, 32, pleaded not guilty on Monday to charges of making false statements to federal officers and entering restricted property after she was arrested on March 30 at the Palm Beach resort. She was arrested with two foreign passports, four cell phones, and allegedly had a thumb drive with malware.

During Monday’s hearing, Assistant U.S. Attorney Rolando Garcia acknowledged that the malware could have been a “false positive” based off of an FBI analysis of the thumb drive, but acknowledged that Zhang got “within arm’s length” of the club’s reception computer. The federal prosecutor said more charges are “possible.” “It does appear to the court that Ms. Zhang was up to something nefarious,” U.S. Magistrate William Matthewman said Monday before denying her request for bond, saying he believes she would flee to China if released.