This is being reported from Bloomberg News:
Ukraine said its troops attacked and partially destroyed an armed convoy that had crossed the border from Russian territory.
Ukrainian government troops engaged the vehicles that had arrived overnight through a rebel-held section of the border, Andriy Lysenko, a spokesman for the country’s military, told reporters in Kiev today. Ukrainian soldiers continue to come under shelling, including rounds fired from Russia, he said.
The government in Kiev has for months said that separatist rebels in its easternmost regions are receiving support from Russia, which backs them with artillery fire. Russia has repeatedly denied any involvement in the Ukrainian unrest.
I haven't seen any other news source confirm this yet, but the stock market is taking a hit over the news.
Update: I still don't see any other news organization reporting this so I'm beginning to have some doubts about the accuracy, but I'm still looking for confirmation.
UPDATE:11:42 USA today is now reporting the story. Looks like the proverbial shit is about to hit the fan in Ukraine:
Ukrainian troops on Friday "destroyed" part of what Kiev says was a Russian armed convoy that crossed into Ukraine around the same time as a truck convoy of humanitarian aid reached the border, according to Andriy Lysenko, spokesman for Ukraine's National Security Defense Council.
Atthe same time,Ukrainian President Petro Poroshenko told British Prime Minister David Cameron on Friday that a "significant" part of the Russian armored column had been destroyed, according to the Ukrainian leader's website, Reuters reports.
...
A reporter for The Guardian said he saw a column of 23 armoured personnel carriers, supported by fuel trucks and other logistics vehicles with official Russian military plates, crossing into Ukraine "through a gap in a barbed wire fence that demarcates the border."