FBI Director Christopher Wray and other intelligence community officials warned about China’s increased capability to interfere in U.S. elections in separate classified hearings with the Senate Intelligence Committee this week, two sources familiar with the hearings tell Axios.

What we're hearing: Wray and other officials cited concerns that China is developing the ability to interfere with local election systems and target members of Congress to influence China policy, sources said.

• Wray briefed committee members on Tuesday afternoon, and the other intel officials, including William Evanina, the director of the National Counterintelligence and Security Center (NCSC) briefed them on Wednesday.
• An official with the Office of the Director of National Intelligence, which includes the NCSC, said it has been providing "robust intelligence-based briefings on election security to the presidential campaigns, political committees, and Congressional audiences" but declined to comment on the details.
• A spokesman for Senator Marco Rubio (R-Fla.), acting Chairman of the Senate Select Committee on Intelligence, told Axios that Rubio is "increasingly concerned about how China is expanding its influence and interference efforts in America. They have a proven capability to carry out cyber attacks and spread disinformation and the clear intent to influence our government policies and pressure policy makers, including members of Congress."
• "They have resources which are far greater than those of Russia," his spokesman added.
• The FBI declined to comment.

Why it matters: China is increasingly becoming a top threat to U.S. election security. "Our adversaries learn from one another," a source familiar with one of the hearings told Axios.

• But intelligence officials still view Russia as the leading threat.

On Friday, Evanina said China, Russia and Iran present the most pressing threats for election interference in the 2020 presidential race.

• He noted that China "is expanding its influence efforts to shape the policy environment in the United States, pressure political figures it views as opposed to China’s interests, and counter criticism of China. Beijing recognizes its efforts might affect the presidential race."

The big picture: The Senate Intelligence Committee has been probing the threat of China interfering in U.S. elections for months, the sources say, and its investigations have picked up speed in recent weeks given that the elections are less than 100 days away.

The backdrop: Prior to the 2018 midterms, President Trump and some top administration officials also warned that China was attempting to influence those elections, Axios’ Bethany Allen-Ebrahimian writes.

• But the administration provided little evidence to support that claim, leaving many observers skeptical.
• This year's warning, however, comes from top law enforcement and intelligence chiefs. And it follows a series of social media disinformation campaigns perpetrated by China and aimed at influencing foreign populations, a modus operandi China seems to have learned from Russia.

What's next: Senate Majority Leader Mitch McConnell, in consulation with the Trump administration, has scheduled time over the next few days for Senate-wide, classified briefings about foreign election interference and political influence, as well as efforts to protect the 2020 elections.

• The briefings will include Evanina and an interagency team from the FBI, Department of Homeland Security and the intelligence community.