Have they dug up graves or found the remains of dead people? The article didn't say so I am not sure how they know that they are tombs. In either event it has been postulated that the Israelites that were scattered abroad from the Northern Kingdom migrated through this area and The Bible says that they were told to place waymarks on the routes that they were taking so that someday they could return back to Israel.
___________________________________________________ Jer 31:21 Set thee up waymarks, make thee high heaps: set thine heart toward the highway, [even] the way [which] thou wentest: turn again, O virgin of Israel, turn again to these thy cities.
___________________________________________________ Isa 43:5 Fear not: for I [am] with thee: I will bring thy seed from the east, and gather thee from the west;
Isa 43:6 I will say to the north, Give up; and to the south, Keep not back: bring my sons from far, and my daughters from the ends of the earth;
The exiled tribes removed from Israel by the Assyrians were scattered; some were sent into the Crimea, and possibly Colchis (Herodotus remarks about the practice of circumcision there); but the smoking guns of course are the Pillars of Ashoka (3rd c BC) two or three of which are inscribed in Aramaic — in what is now Afghanistan.