What does Jeremiah 49:3 mean?

Cry out, Heshbon, because Ai is destroyed! People of Rabbah, scream and mourn. Put on funeral clothes and run around in panic, because Milcom will go into exile, along with his priests and officials. Jeremiah 49:3 - Modern Text Bible

(The Ammonites are told to mourn because their god, their leaders, and their people will all be taken away.)