President Donald Trump's Mar-a-Lago resort is seen on April 03, 2019 in West Palm Beach, Florida. (Photo by Joe Raedle/Getty Images)
West Palm Beach, Florida CNN  — 

A thumb drive obtained from the woman charged with breaching security at President Donald Trump’s Mar-a-Lago resort may not have contained malware after all, federal prosecutors admitted in federal court Monday.

Yujing Zhang, 33, is charged with unlawfully entering a restricted zone and lying to Secret Service agents.

After her arrest, court filings alleged that she was carrying a thumb drive with malware, but it may have actually been a “false positive.”

Prosecutor Rolando Garcia said that when they ran the same test again, it did not produce the same result. They’ve since sent the device to Washington for further analyses, according to Garcia. The US Attorney’s Office of the Southern District of Florida declined to answer CNN’s follow up questions.

Nevertheless, federal magistrate judge William Matthewman denied bond Monday, stating that he believed Zhang had “nefarious intentions” when she allegedly entered Mar-a-Lago illegally late last month. Matthewman called her an “extreme and serious flight risk.”

“Frankly, there is no reason for her to stay in the US if she is released on bond,” Matthewman said.

Zhang pleaded not guilty on all charges.

The judge said he considered many factors in deciding to deny bond, including that the US and China do not have an extradition treaty and the facts of the case.

Zhang was arrested March 30 on the grounds of Trump’s resort with four cell phones, a laptop and other devices in her possession. She claimed she was there to attend a “United Nations Friendship Event,” and that the reason she had all of that equipment on her at the time was only because she did not want to leave all of it back in her hotel room.

But any benefit of the doubt vanished in the eyes of the court on Monday, when prosecutors said they have proof that Zhang knew the event had been canceled two days prior to her leaving China, as well as because of the trove of additional electronics – including a signal detector to detect hidden cameras – and thousands of dollars in cash that were found in her hotel room.

Zhang, who told the court she works in finance and owns a home in Shanghai, was shackled by hands and feet, appeared stoic throughout, and did not react upon her denial of bond.

And though she received the aid of a Mandarin translator, Zhang forcefully and clearly said in English at one point, “I don’t know what that means,” when Garcia said that she had been within “arm’s reach” of a computer inside Mar-a-Lago.