Ezekiel 4:2-3

and lay siege against it, and build forts against it, and cast up a mound against it; set camps also against it, and plant battering rams against it round about.

And take thou unto thee an iron pan, and set it for a wall of iron between thee and the city: and set thy face toward it, and it shall be besieged, and thou shalt lay siege against it. This shall be a sign to the house of Israel.