Some updates from the front. There is pretty amuch media blackout on the Ukrainian side, and the Russians are reporting massive losses among "NATO troops". What I can tell and confirm from limited snippets is that the fighting began to escalate on May 10th, with Russian forces aiming to show the U.S. Special Representative for Ukraine, Kurt Volker who was visiting Ukrainian front lines a couple of days ago who's the boss.
Ukrainians were ready for the above scenario and inserted recon teams behind Russian lines. This tactics paid dividends, as Ukrainian troops managed to intercept, destroy, and in one case even capture Russian mortar battery.
120mm mortars captured by the recon unit of the 30th infantry brigade.
Without effective mortar support Russian lines broke in several places. According to the Ukrainian official press releases, "Ukrainian troops improved their positions in a few places". That's it.
It looks like the biggest gains were made by the 24th infantry brigade operating near Horlyvka.
In order to blunt Ukrainian advance, Russian command ordered the so-called "15th International Brigade" to attack Ukrainian positions in Avdiivka industrial zone. The attack failed even before it started when Ukrainian paratroopers and "Right Sector" volunteers managed to track down and kill the Russian brigade commander and most likely his staff as well.
Russian national, Oleg Mamiev, a native of North Osetia call sign "Mamai" commander of the 15th Brigade will not be murdering anyone anymore.
After suffering setbacks at the front, Russian artillery (122mm SPGs or D-30s howitzers) opened fire on civilian areas behind Ukrainian lines killing and maiming several civilians in the process. Ukrainians conducted anti-battery fire in kind.