West Palm Beach, Florida (CNN) Yujing Zhang, the woman who allegedly breached security at President Donald Trump's private Florida club while carrying Chinese passports and a flash drive containing malware late last month, had a signal detector, other electronic devices and thousands of dollars in cash in her hotel room, federal prosecutors said Monday, suggesting the possibility she was trying to spy on the US.

Zhang appeared at a detention hearing in a Florida federal court Monday afternoon looking shaken and anxious in her jail uniform and handcuffs, her defense attorney presenting a receipt that she had paid $20,000 dollars to a private businessman to attend a canceled Chinese-American "friendship" event at the private club.

Prosecutors say they found multiple electronic devices in her hotel room, including a signal detector that can seek out and detect hidden cameras, another cell phone, nine USB drives and five SIM cards. There were also several credit cards in her name in the room--at the upscale Colony Hotel a block from the beach. She also had more than $8,000 in US and Chinese currency, with $7,500 of it in $100 bills.

Prosecutors have called Zhang a flight risk because she has next to no ties to the US. The federal magistrate judge who held the hearing Monday will decide next week if Zhang should stay in jail until she is tried, or be released to live in the US as she awaits trial.

Zhang, 32, has not yet entered a plea to the criminal charges she faces, and prosecutors said they plan to formally indict her in the coming week.

"She lies to everyone she encounters," prosecutor Rolando Garcia said.

"Her ties are all in China," he later added.

Zhang arrived in Newark on a flight from Shanghai on March 28, Garcia said. She went to Mar-a-Lago on March 30. This wasn't the first time she visited the country in recent years.

Zhang arrived at Mar-a-Lago via taxi-to "acquaint" herself with club grounds, her defense attorney said, before the planned private but canceled event, which promoters had pledged the President's sister would attend. After giving the Secret Service her last name and showing her passports, making it through two security checkpoints and taking a golf cart ride with a club staffer, the Secret Service found she was carrying a thumb drive with malware, as well as a laptop, an external hard drive and four cell phones. She was charged with two counts -- making false statements to federal authorities and a misdemeanor offense of entering a restricted area without authorization.

She has not been charged with any offenses that nod to international spying. However, the FBI has been investigating the Zhang incident as part of a Chinese espionage effort.

Secret Service missteps

In the first hour of the hearing, Zhang's defense attorney focused on how the Secret Service let her on the property, determined Zhang may have lied, and steps they took in questioning her that afternoon and night.

"The only thing Ms. Zhang did was give a very common Chinese name" to gain access to Mar-a-Lago, public defender Robert Adler said in court. "And, it was decided she be let in. I don't understand how this could support a trespassing charge."

The agent who questioned her, Samuel Ivanovich, testified on Monday for about an hour about what happened that day.

Adler used Ivanovich's testimony to show flaws in the Secret Service's procedures. For instance, a Secret Service agent who spoke Mandarin was called in to help with translations hours into Zhang's questioning. Adler also had Ivanovich admit that the agency that protects the President largely relied on Mar-a-Lago staff to determine whether to admit Zhang, didn't see red flags in the devices she carried when they showed up at a metal detector checkpoint inside the club, and asked no further questions of Zhang when she first arrived once they believed she was related to another club member with the same last name. Adler pointed out her name was extremely common in China--one of the three most common last names in the country.

The Secret Service has no audio security recordings of its interactions with her and what she said on the grounds of Mar-a-Lago, Ivanovich also said.

Ivanovich, being questioned about the malware allegedly found on Zhang's thumb drive, said the agent examining the drive found a malicious "file" that began to install onto an agent's computer, and the agent looking at it said that had never happened before, and it was "very out of the ordinary" when conducting a criminal analysis.

The agent looking at the drive had to stop the analysis and shut down his computer.

Mar-a-Lago security

Trump has described the Zhang case as a "fluke situation," but the case so far has highlighted the possibility of security flaws at Trump's private club.

Zhang talked her way into the club, carrying a large number of electronic devices including malware on a thumbdrive. At first, she told a special agent at Mar-a-Lago she wanted to visit the pool at the beach club--even though she wore a long gray dress and had no bathing suit. The Mar-a-Lago beach club manager then noted her last name matched that of a club member, and the club waved her in, believing her to be the club member's daughter, and "due to a potential language barrier issue," authorities wrote in her criminal complaint.

A golf cart shuttle driver then took her to the club's main reception area, where Zhang told a Secret Service agent she sought to attend a "United Nations Friendship Event" on the premises.

Adler showed in court fliers that advertised in Chinese a similar-sounding event for that day. The fliers included a photo of Trump's sister, and may have come from a Florida businesswoman and a Chinese businessman who promoted events and attempted to profit off of political heavyweights he met in America. In essence, Adler said, the businesswoman Cindy Yang "bundled" the Mar-a-Lago event, then a man named Charles Lee "repackaged" the event, collecting $20,000 from Zhang so she could attend. Adler had a wire transfer receipt from Chinese contacts that showed this, he said to the judge.

Zhang had told authorities who were questioning her that her Chinese friend "Charles," whom she communicated with over a chat app, had sent her from Shanghai to speak with the President's family about Chinese and American foreign economic relations, according to the complaint.

The case comes as Democrats in Congress press for more information about security at Mar-a-Lago and, separately, for an FBI investigation into Florida businesswoman Li "Cindy" Yang's efforts to interact with Trump, after she appeared to have pitched to Chinese clients the opportunity to interact with the President and spend time at Mar-a-Lago with the President at a Super Bowl party.

Previous hearing

Zhang's two court appearances have run unusually long, with more details than usual about her and her case being presented to the judge. At the previous hearing, she admitted to owning a BMW and a home in China worth more than 1 million American dollars, and asked extensively about how she may get in contact with an attorney or find phone numbers of contacts in America if she were detained in a Florida jail.

She said she worked as an investor and consultant who sought to develop business contacts in the US, but kept some money in a Wells Fargo account here--thousands less than what she actually had in her hotel room, the prosecutors say.

She has been in jail since her arrest, with a court-appointed public defender representing her.

The federal magistrate judge, William Matthewman, even noted the astuteness of her questions and her intelligence at the previous hearing. There's been some dispute over how well Zhang speaks and understands English, and the court has provided her with a language interpreter at both court hearings.