A top Ukrainian army officer said a "full-scale invasion" of his country was under way Thursday, as a U.S. official said up to 1,000 Russian troops had crossed Ukraine's southern border to fight alongside pro-Russian rebels.
NATO released satellite images which it says show Russian self-propelled artillery units moving inside Ukrainian territory.
— OutFrontCNN (@OutFrontCNN) August 28, 2014
And new video shows what the Ukrainian government says is a Russian tank farther south, where a new front is opening up in the conflict.
OutFront, Senator Ben Nelson, who just returned from a fact-finding mission to Ukraine.
On a day which saw a fighter jet shot down in Ukraine, on Thursday evening Erin Burnett welcomed CNN's Nick Paton Walsh to report "OutFront" from Donetsk.
Less than a month since the downing of Malaysian Airlines Flight 17, Walsh noted that the missile system used in both aircraft attacks appears to be similar, if not identical.
Additionally, the situation on the ground in Ukraine remain tenuous as fighting continues to rage near the wreckage of Flight 17, while this week also saw a rebel leader quite in bizarre and unexpected fashion.
For Walsh's full report on the latest developments, including the expected next movements from Russia, watch the above video.
While reporting for "OutFront" on Tuesday evening, CNN's Nick Paton Walsh witnessed nearby gunfire in Donetsk, Ukraine.
As fight ensued during the early hours of the morning, Walsh noted that this was "the most sustained gunfire we’ve heard" near the center of the city.
This comes as the Russian military is nearly doubling in size along the border with Ukraine.
Watch the video above as Nick Paton Walsh pauses multiple times to acknowledge a barrage of gunfire.
CNN's Erin Burnett speaks with Gen. Jim Jones, former National Security Adviser to President Obama about the first time President Barack Obama met Vladimir Putin.
On Tuesday, President Obama announced the U.S. is slapping Moscow with new sanctions in retaliation for Putin's support of rebels in Ukraine.
Are these new sanctions going to make a difference?
OutFront is Ben Judah. He's spent the past three years researching Vladimir Putin and wrote the recent Newsweek article, "Behind the Scenes in Putin's Court: The Private Habits of a Latter-Day Dictator."