The Lvov-Sandmierz offensive was
in full bloom with the 3rd Guards Tank Army recently exploiting a weak gap in the
German defense lines, known as the Koltov Corridor. On 18 July, a second major
blow hit Army Group North Ukraine under the command of Col.Gen Josef Harpe
as the southern wing of Rokossovskiy´s 1st Byelorussian Front went over to the
offensive around Kovel. The attack began with a short but intense artillery barrage
and afterwards came the tank-supported columns.