WASHINGTON, DC — China is making an “unprecedented effort to influence American opinion” during the ongoing congressional elections season and poses the “most long-term counter-intelligence threat” facing the United States, top U.S. national security officials told lawmakers Wednesday.

During a Senate panel hearing, U.S. Department of Homeland Security (DHS) Secretary Kirstjen Nielsen addressed the “threats that we see from nation states … with respect to our elections,” telling lawmakers, “China absolutely is on an unprecedented, or exerting unprecedented effort to influence American opinion … we have not seen to date any Chinese attempts to compromise election infrastructure.”

Asked whether China represents a more significant threat than Russia, FBI Director Christopher Wray, who testified before the Senate Homeland Security and Government Affairs Committee alongside the DHS chief, added:

China in many ways represents the broadest, most complicated, most long term counter intelligence threat we face. Russia is in many ways fighting to stay relevant after the fall of the Soviet Union. They’re fighting today’s fight. China is fighting tomorrow’s fight and the day after tomorrow and the day after that, and it affects every sector of our economy, every state in the country and just about every aspect of what we hold dear.

Last month, President Trump accused China of trying to meddle in the November 6 congressional elections, arguing that Beijing does not want Republicans to do well.

“China has been attempting to interfere in our upcoming 2018 election, coming up in November. Against my administration,” the Republican president declared at a September 26 United Nations Security Council meeting. “They do not want me or us to win because I am the first president ever to challenge China on trade and we are winning on trade.”

Beijing rejected the accusations.

Currently, the U.S. Department of Justice (DOJ) is investigating Russian activities during the 2016 presidential election, particularly whether the Kremlin cooperated with the Trump campaign to influence the vote.

A similar probe by the Republican-led House Intelligence Committee already determined that there is no evidence of collusion between the Trump campaign and Russia.

U.S. intelligence officials did find that Moscow has employed widespread campaigns to influence the American elections.

Russia denies the accusations.