Are the rebels going to retreat or do they get reinforced?

(For UPDATES scroll down.)

The Seversky Donets' river and surrounding areas are a natural barrier. Only on several locations there are bridges. This means it provides safe protection as a route for either a retreat or for reinforcements.

From Slovyansk this route goes to the East to Russia alongside this line.

Along this route there are several activities.

Today a bridge near Pryvillya has been destroyed (yellow marker in the north), limiting the possibilities to cross.

#BreakingNews Reports of separatists have blown up the first footbridge across the Seversky Donets river near Pryvillya-Old Krasnyank.
— ConflictReporter (@MiddleEast_BRK) 22 mei 2014

This is the bridge @ #Lisichansk where battle happened & supposedly it was blown up by terrorists. Unconfirmed. pic.twitter.com/tiopzgCskl
— lennutrajektoor (@lennutrajektoor) 22 mei 2014

#BreakingFootage Ukrainian army #MilMi24 step into battle over #Lisichansk, #Luhansk oblast. https://t.co/JfFZm35Hcp #Ukraine
— ConflictReporter (@MiddleEast_BRK) 22 mei 2014

Unconfirmed report: battles are going on near #Lysachansk & #Rubyzhne (#Lugansk oblast). Bridge is blew up @bannikova_a | EMPR News #Ukraine
— Euromaidan PR (@EuromaidanPR) 22 mei 2014

Rubyzhne and Lysachansk are exactly the areas where the route goes through the barrier. Controlling these cities means you either have this route or block it.

RT @lennutrajektoor 2m #ATO fighter jets are in #Rubezhnoe. It's the next bridge @ #Lisichansk. #Ukraine pic.twitter.com/KvEFGHG9GF #cdnpoli
— Rock Solid Politics (@BradCabana) 22 mei 2014

12:40 #Lisichansk Battle rages on. Heli is flying, shelling Hellfires. Fighter jets spotted. #ATO #Ukraine pic.twitter.com/R1TjXXl5KH
— lennutrajektoor (@lennutrajektoor) 22 mei 2014

Theory circulates in #Rubezhnoe, 2nd bridge @ #Lisichansk, #ATO NG were ambushed, trees fell on road & then attacked. pic.twitter.com/eYc5Guh6Dl
— lennutrajektoor (@lennutrajektoor) 22 mei 2014

Dear Internet, this is #Lisichansk 2nd bridge. It's intact. pic.twitter.com/9bORzJESdZ #Ukraine #ATO
— lennutrajektoor (@lennutrajektoor) 22 mei 2014

Somehow it seems the Ukrainian army has been prepared for this. Because yesterday (21-5-2014) it had already been sending pontoon bridges from Poltava to the region.

Yesterday a boatload of pontoon bridge sections where hauled from Poltava towards #Kharkiv and maybe to #Slavyansk? http://t.co/lkgYxXrkBr
— Citizen of EU (@wavetossed) 21 mei 2014

#BreakingNews (Pro-)Russian forces in Lysychans'k city rush to the frontline to reinforce their ranks. #Luhansk pic.twitter.com/8OXYGFWiFH
— ConflictReporter (@MiddleEast_BRK) 22 mei 2014

These are only 2 APCs and one truck. But they have not been seen before, as far as I know. The next message seems to clarify what is going on. It is about some serious reinforcements...

MIA about numerous attempts to break through the state border by armed gangs from Russian side last night (Ukr): http://t.co/fL3YLCo5g2
— Natalia Melnychuk (@pravolivo) 22 mei 2014

#Tymchuk Massive redeployment of #Doentsk terrorists to #Slaviansk region. Unarmed. Will get arms on site. #Ukraine pic.twitter.com/AHUOkyS2aE
— lennutrajektoor (@lennutrajektoor) 22 mei 2014

UPDATE 24-5
One of the bridges in Severodonetsk has been blocked. This seems strange, because this is right ON the route...

#Severodonetsk, Lugansk oblast is blocked from ROW https://t.co/jpKB0jgOVi | EMPR News #terrorism #Ukraine pic.twitter.com/jfdY1am6CU
— Euromaidan PR (@EuromaidanPR) 24 mei 2014

An interactive map of this area can be found here.

Also see an earlier report: Are the rebels in Slovyansk preparing a retreat?
Also see: Several Ukrainian checkpoints attach across Donetsk area