He alerted Augereau to concentrate the VII Corps in readiness to march. The emperor also ordered Marshal François Joseph Lefebvre and the X Corps to protect Thorn (Toruń) and the lower Vistula. On 19 January, the Russians finally appeared out of the forests, driving Ney's troops from Schippenbeil. After detaching 3,000 men to link with the 6th Division, Bennigsen commanded about 63,000 troops, while L'Estocq had 13,000 in the area. On the 21st, Bennigsen's advance elements were in Heilsberg (Lidzbark Warmiński) with L'Estocq on his right flank. The three Russian advance guards were led by Major Generals Markov, Michael Andreas Barclay de Tolly, and Karl Gustav von Baggovut. Though his cavalry under General of Brigade Auguste Francois-Marie de Colbert-Chabanais was roughly handled, Ney managed to escape southward to Neidenburg (Nidzica). Having brushed aside Ney, the Russians bore down on Bernadotte's corps. On 24 January, Markov mauled a French unit at Liebstadt (Miłakowo), capturing 300 Frenchmen. Bernadotte quickly assembled General of Division Pierre Dupont's division and General of Brigade Jacques Léonard Laplanche's dragoons at Preussisch Holland (Pasłęk) on his left flank in the northwest. On his own initiative, Bernadotte's chief of staff General of Brigade Nicolas Joseph Maison alerted the I Corps center and right flank. Maison directed General of Division Olivier Rivaud to concentrate his division at Osterode on the right, while General of Division Jean-Baptiste Drouet gathered his troops at Saalfeld (Zalewo) in the center. Maison held General of Brigade Michel Marie Pacthod's 8th Light Infantry Regiment at Mohrungen, while calling Sahuc's other dragoon brigade from the right flank toward the center. Battle At noon on 25 January, Markov approached Mohrungen with the right wing advance guard. From prisoners taken at Liebstadt, the Russian general knew that Bernadotte was concentrating at Mohrungen. In fact, the French marshal held the town with nine infantry battalions and 11 cavalry squadrons. This force comprised units of all three I Corps divisions, including the 8th Light Infantry of Rivaud's division plus elements of both Drouet's and Dupont's divisions. When Markov appeared, Bernadotte immediately advanced northward to engage his enemy. He ordered Dupont to march from Preussisch Holland to hit the Russian west flank with the bulk of his division. Markov's advance guard included the Ekaterinoslav Grenadier Regiment, the Pskov Musketeer Regiment, the 5th, 7th, and 25th Jäger Regiments, six squadrons of the Elisabethgrad Hussar Regiment, four-foot artillery batteries, and one horse artillery battery.