KHARKIV, Ukraine - In the past three days, Russian troops, backed by fighter jets, artillery and lethal drones, have poured across Ukraine’s northeastern border and seized at least nine villages and settlements, and more territory per day than at almost any other point in the war, save the very beginning.

In the past three days, Russian troops, backed by fighter jets, artillery and lethal drones, have poured across Ukraine’s northeastern border and seized at least nine villages and settlements, and more territory per day than at almost any other point in the war, save the very beginning.