'Broken up' in the Bible

So Rab-shakeh returned, and found the king of Assyria warring against Libnah, - for he had heard that he had broken up from Lachish.

then was the city broken up, and all the men of war fled by night by way of the gate between the two walls, which is by the garden of the king, the Chaldeans being near the city round about, - and he went the way of the Waste Plain;