SARAJEVO, Bosnia-Herzegovina (AP) — The chief of Bosnia's border police warms that his guards cannot contain the migratory pressure along the country's eastern border with Serbia.

Zoran Galic says the situation could easily escalate and put in danger the overall stability of their politically fragile nation, which is still recovering from war.

Galic told The Associated Press in an interview Tuesday that securing the nation's entire 1,600-kilometer (995-mile) border along a popular migration route into Europe was like the "work of Sisyphus." That was a reference to the Greek mythical hero who was condemned to push a rock up a mountain for eternity only to watch it roll all the way down every time he reaches the top.

He said: "We are in a constant struggle to deter migrants, but they never quit."