Concerns about security and the level of access to President Donald Trump at his private Florida club Mar-a-Lago have been swirling since he was elected, but scrutiny kicked into high gear after the US Secret Service arrested a Chinese woman, Yujing Zhang, who they say was carrying four cellphones and a malware-infected thumb drive at the resort over the weekend.

According to the Miami Herald, a federal counterintelligence probe into possible Chinese intelligence operations targeting Trump spearheaded by the FBI was already underway, and now, it’s been “turbo-charged.”

The probe is also looking at Li “Cindy” Yang, a Florida massage parlor owner who allegedly sold access to President Trump and his family. According to the Herald, the investigation is a broader probe into Chinese nationals doing business in the area and predates both the revelations about Yang and Zhang’s entry attempt.

This isn’t the first time concerns about potential lax security around the president, or his accessibility at Mar-a-Lago, have been raised. Shortly after his inauguration, for example, Trump and Japanese Prime Minister Shinzo Abe discussed their response to a North Korean ballistic missile test within full view and earshot of Mar-a-Lago guests.

In the wake of this latest gaffe, the Secret Service has essentially thrown up its hands and said it’s up to Mar-a-Lago, not them, to figure out who gets in and who doesn’t.

But that hasn’t stopped the FBI —or Democrats — from asking questions about what’s going on there.

A Chinese woman was arrested after getting access to Mar-a-Lago

Here’s why this is all being talked about now: On Saturday, Zhang, a 32-year-old Chinese woman, was arrested while at Mar-a-Lago.

According to the federal complaint, Zhang approached a Secret Service agent around noon and presented two Chinese passports, saying she wanted to go to the pool. The agent confirmed her identity and tried to figure out if she was on the access list for the club.

A manager on duty confirmed that there was someone with the last name Zhang who was a member of the club, but Zhang “did not give a definitive answer” when asked if that was her father. She also wouldn’t say if she was there to meet with anyone, but because of a “potential language barrier issue,” Mar-a-Lago believed her to be a relative of the club member and let her in.

Zhang was let onto the grounds and once there was asked by a receptionist why she was there. She finally said she was there for a United Nations Chinese American Association event that evening.

But the event didn’t exist. That’s when it all began to unravel.

Another Secret Service agent then came into contact with Zhang; she told the agent she was there to attend a United Nations friendship event and presented the agent with a supposed invitation, but it was in Chinese. There was also no such event scheduled. The agent told Zhang she wasn’t allowed on the grounds, during which time, according to the complaint, she “became verbally aggressive with agents” and was detained.

Agents later searched her belongings and found four cellphones, a hard drive, a laptop, and a malware-infected USB drive. Zhang was arrested and charged with lying to a federal agent and knowingly entering a restricted area.

The incident has heightened concerns about the potential national security risks presented by Mar-a-Lago

The Secret Service in a statement on Tuesday said it “does not determine who is invited or welcome at Mar-a-Lago” and that it’s instead the responsibility of the host entity.

“The Mar-a-Lago club management determines which members and guests are granted access to the property. This access does not afford an individual proximity to the President or other Secret Service protectees,” the statement read.

“In such instances, additional screening and security measures are employed,” it continued. “With the exception of certain permanently protected facilities, such as the White House, the practice used at Mar-a-Lago is no different than that long-used at any other site temporarily visited by the President or other Secret Service protectees.”

Also in response to Saturday’s incident, Senate Minority Leader Chuck Schumer and Sens. Dianne Feinstein and Mark Warner sent a letter to FBI Director Christopher Wray (and copied the director of national intelligence and Secret Service director) urging the bureau to “immediately assess national security risks” at the president’s properties.

“This latest incident raises very serious questions regarding security vulnerabilities at Mar-a-Lago, which foreign intelligence services have reportedly targeted,” they wrote.

This has been bubbling for a while

Zhang’s arrest comes on the heels of reports about Yang, the Chinese woman who had reportedly been selling access to Trump.

The New York Times published a report in March detailing Yang’s activities, which Vox’s Ella Nilsen summed up at the time:

Yang got direct access to Trump herself at least two times, posing with the president at his annual Super Bowl watch party last month at Mar-a-Lago and snapping a picture with him at a separate Republican National Committee fundraiser at Mar-a-Lago last March. Yang had to pay $50,000 for her March 2018 dinner and photo with the president. She also founded a company called GY US Investments that promised businesspeople from China access to the White House and Capitol Hill. GY US Investments promised to broker visits at places including the White House, Mar-a-Lago, and the annual shareholder meeting of Warren Buffett’s company Berkshire Hathaway, according to the New York Times.

Yang also used to own the Florida massage parlor where New England Patriots owner Robert Kraft is accused of having solicited sex as part of a prostitution ring sting. The Miami Herald published a report ahead of the Times story about Yang gaining access to Trump and her political engagement after 2016.

Democrats have also asked the FBI to dig into the reports about Yang and her activities. In a March letter, congressional Democrats said the allegations “raise serious counterintelligence concerns.”

“China has frequently used non-traditional intelligence collectors and businesspersons to compromise targets,” Democrats wrote. They requested that the FBI conduct “criminal and counterintelligence investigations into credible allegations of potential human trafficking, as well as unlawful foreign lobbying, campaign finance and other activities by Yang.”

Trump says he’s not worried about Chinese spying at Mar-a-Lago

Trump was asked by reporters on Wednesday whether he’s worried the Chinese might be trying to spy at Mar-a-Lago. He said he’d seen the story and had had a brief meeting but largely brushed it off.

“No, I’m not concerned at all,” he said. “We have very good control.”

But Trump, and all of us, should be worried. Peter Harrell, an adjunct senior fellow at the Center for a New American Security, told the Miami Herald he would be surprised if China and other adversarial governments weren’t trying to get into Mar-a-Lago and the president’s other properties. “There’s a huge trove of information available,” he said.

Trump often visits Mar-a-Lago on the weekends and is known to drop in on events and chat with guests. He moves freely around the grounds and invites other politicians, members of his administration, and foreigners to go there with him. And, as mentioned, he’s not opposed to having some pretty sensitive talks out in the open and in front of guests.

It’s not clear whether any malicious actors have been successful in potential espionage efforts at Mar-a-Lago, but it’s likely they’re trying. And Mar-a-Lago doesn’t seem to be making it particularly difficult.

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