This is only KNOWN and verified vehicles. There might be more of course.
Captured from Ukraine in the beginning of ATO (See this Youtube video). Located at Slovyansk.
2-3 NONAs self propelled mortars
Initially one captured from the Ukrainians, but later destroyed. Received new ones from Russia.
Recieved from Russia. One was lost in an attempt to rain havoc on a village and blame the army for it. One seems to be in Kramatorsk right now.
See this report.
3 T-64Bs, anti-air gun
Crossed the border on June 12th. Located in Donetsk.
See this report and this one.
4 tanks, 6BTRs, 14 trucks 2 guns (see this report)
Crossed the border on June 20th. 2 tanks and 2 BTRs went to Kramatorsk/Slovyansk. Some operating from White chalk hills.
2 tanks and 3 BTRs went to Torez and from there likely engaging towards Amvrosiivka and Marinovka. (See this report.)
2 BTR, 1 BMD, 2 T64b
Captured from Ukraine at Metalist on June 17th and revived. Located in and around Lugansk.
See report here and here and here.
2 tanks, 2 BMPs, truck with 120 mm mortar
First seen in Perevalsk on June 25th. Must have crossed the border independently from June 20th crossing. Destination unknown.
See this report.
This makes 11 tanks, 2-3 NONAs, 11 BTRs 2-3 GRADs, 2 guns, 1 anti-air gun, 1 120mm mortar and whatever they had been transporting INSIDE the trucks of course...
NOTE: when transports are done during the night and driven to final destinations they are not likely to be filmed. It means there might be substantially more hardware than this. But these are RECORDED
If you have any verifiable information about where they are, whether they are destroyed or whether new vehicles arrive, please let me know.
If you see any errors, please let me know.
UPDATEThis video shows another vehicle in Donetsk June 26th:
Сепаратисты несут потери в боях на востоке Украины http://t.co/zB21sI2N3Y pic.twitter.com/YBAxoUSZNRIt is a BRDM-2, an amphibious reconnaissance and patrol vehicle. If it is spotted in Siversk on June 20th, it may have traveled back to Donetsk, because some tanks arrived at Siversk.
— Агентство Рейтер (@reuters_russia) June 20, 2014
Question remains: where did it come from?
UPDATE June 27th: (pro)Russians lost two and got at least three tanks.
Also see: Russian armor movements close to Ukraine's border.