Russia may test out its latest cyber-weapons in the upcoming elections in Ukraine, with an eye toward using them to interfere in and manipulate the 2020 U.S. presidential campaign, reports The Washington Post.

In an interview, Anders Rasmussen, former NATO secretary-general and Danish prime minister, called Ukraine “ground zero when it comes to foreign meddling in elections.”

“We don’t know in advance which technologies Russia will use. We do know that they will come up with more and more sophisticated methods. That’s why we need to be at the forefront by witnessing what they are actually doing,” he said.

Ukrainian officials fear that Kremlin operatives could hack into candidates’ computer networks and interfere with communications, electrical grids and air travel during the elections that begin March 31. They are also likely to circulate faked or doctored audio and video files that look “amazingly authentic” and readily go viral on social media.

Russia might also hack directly into the country’s election system “to cast doubt on the validity of the real results,” says the Post, noting that such hacking happened during Ukraine’s last presidential election.

The newspaper notes that among the crimes former Trump campaign manager Paul Manafort will go to prison for is the work he did for a pro-Russian political party in Ukraine.

“Special counsel Bob Mueller’s team alleged last month that [Manafort] was still working on Ukrainian political matters in 2018, even after his indictment,” the Post says.

Plus, it says, unlike Americans, “Ukrainians must also worry about the real possibility of Russia using conventional military force … or activating sleeper cells inside Kiev to conduct sabotage and foment violence in the streets.”

Rasmussen, the former NATO chief, admits the alliance was surprised five years ago when Russian President Vladimir Putin ordered an invasion of Ukraine and annexed its strategic Black Sea peninsula, Crimea, which remains in the hands of Russian forces.

As for the U.S., he says the main Russian aim is to “sow mistrust and lack of confidence in our democratic institutions and our democratic process.”