CNN's Frederik Pleitgen has witnessed what he describes as "a lot of very ominous movement" on the ground in Russia, near northeast Ukraine.
"We've seen ... military trucks, who have actually had their license plates on backwards. They turned the license plates around, which could be them trying to mask some sort of movement," Pleitgen told CNN.
"The Russian military really [is] in a position where it certainly seems as though they could strike at any point in time," he added.
Meanwhile, further south, near Donetsk, Pleitgen noted other examples of assembled Russian military.
"You see a lot of Russian convoys there that seem to be forming," he said. "[It is] unclear whether or not they've gone over the border yet, the way that all of this could happen is, you might have two areas where the Russians might try to go across the border."
Pleitgen closed his live report by offering a statement on the general atmosphere in the region.
"You really feel how things are getting more tense here by the minute," noted Pleitgen, adding, "you certainly also see that the Russian military is on the ground here, and certainly at least seems to be in a position to be able to strike at any point in time if Vladimir Putin chooses to order that."