After rapidly assembling at first light, reinforced by reconnaissance battalion, Peiper opened the attack on Stoumount as 9.00 a.m. (CET). To the left of the road leading to the village was a steep drop off which redistricted the movement of the panzers deployed on the flank, but they almost reached he village undercover of the early morning mist before they were spotted and the American anti-tank guns and artillery opened up from the outskirts and the edge of a wood to the north. The first panzer - a panther - to get into the the village reached the church, where it was knocked out by a 90mm anti-tank gun. The battle went on for two hours, with the infantry attacking south while panzers advanced along the road, before the defense was finally breached and the village penetrated. The Americans suffered some 250 casualties and about a hundred taken prisoner.
With characteristic efficiency Peiper wasted no time in dispatching a probing force forward on the heels of the Americans, and a few Panthers and SPWs began to roll down the road towards the railway station beyond the village. It was from here, though, that the Americans planned to start a counter attack and where a company of the 704th Tank Battalion commanded by Lieutenant Colonel George K. Rubel (which had been hastily equipped with tanks collected from Sperimont Ordnance Depot), plus a company of the 1st Battalion, the 119th Regiment, and two AAA Batteries - the 110th and 143rd - formed a strong roadblock awaiting the oncoming armor. All around lay the litter of equipment discarded by the shattered 3rd Battalion of the 119th regiment during its retreat from the village itself.
a about 3.00 p.m., just behind the last of the retreating Shermans, a Panther suddenly appeared out of the fog almost on top of the American forces. The Panthers over-confident crew were slow to react and one of the Shermans fired first. At that range the Panther stood no chance and the shell ricocheted down from the gun mantlet, killing the driver instantly. Second later the Panther behind it also brewed up. As a third came out of the mist it entered the sights of a tank destroyer: the shell struck the road, flew up off the ground and penetrated the hull floor. A second shot hit the muzzle brake and the end of the barrel shattered as the tank burst into flames.
This action marked the furthest point west reached by Kampfgruppe Peiper. It was the supply situation which ruled out further progress. Until supplies could be brought up, all that could be done would be to hold existing positions. Knittel’s force was ordered back to Stavelot to secure the supply route and to keep the bridge open. The 1. Komapnie of SS-Pz.Rgt. 1 was to hold positions reached at Stoumount railway station and the village, while 2. Kompanie was responsible for securing Le Gleize against attack from the north and north-east. Meanwhile Flak-Sturm-Abeilung 84 was to block the area around Cheneux to protect the Amblève crossing. Supporting the panzers at Stoumount and reinforcing the troops at Cheneux were grenadiers of the III. Battalion, SS.Pz.Gren.Rgt.2.
Since the afternoon Stoumount had constant artillery and mortar fire and, towards dusk, as fighting to the west gradually intensified, Peiper realized that his weak forces were unable to maintain their hold on the three kilometers between the village and the nearby railway station. Reluctantly, he therefore ordered the troops be withdrawn that evening, first to a hairpin bend along the road, and finally at 9.00 p.m. to the edge of the village. Kampfgruppe command post was located in a house near the Froide-Cour château, the château itself being used as a clearing and collection point for prisoners.
Earlier about midday, Peiper had sent out a small patrol north from La Gleize. The Sd.Kfz.s 250s had passed through Borgoumont, and at Cour the grenadiers learned from the villagers the precise location of a huge fuel depot. Pressing on, they soon ran into the troops guarding the petrol and after a short skirmish withdrew to La Gleize. In a desperate need for fuel, Peiper was halted just short of two million gallons yet he made no further attempt to reach it. He later stated that, though he had not known of the dump north of Stavelot, the map he was given before the start of the offensive was marked with the supply installation at Bülligen and with the one north of La Gleize. By December 19 the Stavelot dump had been entirely shifted when the patrol approached. This operation had then gone ahead without any more interruptions and was completed within a couple of days.