Two US sources told CNN on Monday that the US continues to witness Russia making movements in the field that are consistent with plans to invade Ukraine.

According to a US person familiar with the newest intelligence, military preparations are continuing pace, with “no slowdown.”

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Another US official claimed that the “tactical indicators” that Russian personnel in the field are using are what they would do “if they were told to invade.” According to the person, the US is now watching for “larger actions” beyond field activity that could suggest future kinetic activity on a greater scale.

Other indicators, such as electronic jamming and widespread cyberattacks, have not yet been observed, according to multiple sources. The sources cautioned that orders can always be withdrawn or that it could be misinformation meant to confuse and mislead the US and allies.

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According to several reports, further symptoms such as electronic jamming and extensive cyberattacks have yet to be seen. The sources warned that instructions might be revoked at any time, or that the information could be false in order to confuse and mislead the US and its allies.

According to two US officials and another source familiar with US intelligence, the US has intelligence showing orders have been transmitted to Russian commanders to proceed with an attack on Ukraine.

The intelligence about the directive to tactical commanders and intelligence agents is one of several indicators the US is keeping an eye on to see if Russian invasion preparations are nearing completion.

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A Russian invasion on Ukraine, according to national security adviser Jake Sullivan, may start “in the coming hours or days” and would be “extremely violent.”

“We believe that any military operation of this size, scope and magnitude of what we believe the Russians are planning will be extremely violent. It will cost the lives of Ukrainians and Russians, civilians and military personnel alike. But we also have intelligence to suggest that there will be an even greater form of brutality because this will not simply be some conventional war between two armies: It will be a war waged by Russia on the Ukrainian people, to repress them, to crush them, to harm them,” Sullivan said on NBC’s “Today Show” on Monday.