Bulgaria' s army has started to dig out its vintage tanks produced by Maybach, in order to protect them from robberies.

Army officials reported that a number of Panzer IV tanks, equipped with Maybach engines and previously buried near the southern Bulgarian border as stationary guns, have already been dug out and transported to a secure military base.

All tanks will be in a safe place before the end of February but it is still unclear what their future will be, the army said.

According to experts, there are few tanks of the same type in the world still outside the military museums and robbers could make a good profit by selling parts of the machines to collectioners.

In November, Bulgaria's police arrested two German nationals and a Bulgarian army major over stealing and exporting abroad a whole Panzer IV tank and attempting to do the same with a second one.

In January , police launched another investigation over a stolen turret of a third vintage tank.