SAN FRANCISCO (CBS SF) -- It didn't take long for President Donald Trump to take aim at Democratic Sen. Dianne Feinstein over a report that one of her former employees may have been passing information to the Chinese government.
On Friday night, the President tweeted: "Dianne is the person leading our Nation on "Collusion" with Russia (only done by Dems). Will she now investigate herself?"
On Saturday, Feinstein fired back on the social media platform posting:"The FBI told me 5 years ago it had concerns that China was seeking to recruit an administrative member of my Calif staff (despite no access to sensitive information). I took those concerns seriously, learned the facts and made sure the employee left my office immediately."
"Compare that to your actions: attacking the FBI and refusing the advice of your national security team. SAD! I appreciated then and now the diligent work of our law enforcement and intelligence agencies and acted in the best interests of the country. Give it a try!"
Trump also took aim at Feinstein in a speech over the weekend in Ohio.
"And speaking of China, it's just come out that the Democratic leader and the leader of the Russian investigation, Dianne Feinstein, had a Chinese spy as her driver for 20 years," he told the crowd. "And she's leading the Russian investigation, if that's what you call it. How about it, no no, she's leading the Russian witch hunt. A Democrat-inspired witch hunt."
He further implied that the long-time Democratic senator had lost the moral high ground to raise any questions about the Russian investigation.
"And then she says to me, "Well, what did you know about this and that" - I mean give me a break, come on folks. Come on," Trump told the crowd.
New details emerged last week about how a mole for the government of communist China managed to stay by Feinstein's side. It happened five years ago, but additional information is just surfacing about how the Bay Area senator's office was infiltrated by a Chinese spy.
The Bay Area is a hotbed for Russian and Chinese espionage. Late last year, the feds shut down the Russian consulate in San Francisco.
You may remember the thick black smoke that billowing from building before Russian diplomats turned it over to authorities, presumably produced by burning documents.
Now, all eyes are on Chinese intelligence in the Bay Area after the website Politico reported that a staffer for Feinstein turned out to be a Chinese spy who reported back to the government officials about local politics.
The San Francisco Chronicle uncovered additional details in a column written by reporters Phil Matier and Andy Ross.
The column revealed that the Chinese spy was Feinstein's driver who also served as a gofer in her Bay Area office and was a liaison to the Asian-American community.
He even attended Chinese consulate functions for the senator.
Feinstein -- who was Chair of the Senate Intelligence Committee at the time -- was reportedly mortified when the FBI told her she'd be infiltrated. Investigators reportedly concluded the driver hadn't leaked anything of substance and Feinstein forced him to retire.
Former FBI agent and KPIX 5 security analyst Jeff Harp said he was not surprised.
"Think about Diane Feinstein and what she had access to," said Harp. "One, she had access to the Chinese community here in San Francisco; great amount of political influence. Two, correct me if I'm wrong, Dianne Feinstein still has very close ties to the intelligence committees there in Washington, D.C."
Harp ran counter espionage for the FBI in the Bay Area. He said in addition to traditional political intel and diplomatic secrets, Bay Area spies are often focused on things like R&D, technology and trade secrets.
"They also have an interest in the economy here. How to get political influence here," said Harp. "What's being developed in Silicon Valley that has dual-use technology. All of that is tied to the Bay Area."
Feinstein's office would not comment on the story, saying they do not address personnel matters or investigations, but they added that none of their California offices staffers had ever had security clearance.
The FBI declined to comment on the story.
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