The Lithuanians compel two Russian corps to evacuate Samogitia.--Operations of general Chlapowski in the department of Bialystok.--Capture of Bielsk.--Defeat of a Russian force at Narewka and expulsion of the enemy from the department.--Recapitulation of the forces which had been sent into Lithuania.--Operations of the main army.--Attempt of marshal Diebitsch to intercept Skrzynecki on his retrograde march, by a diversion to Ostrolenka.--General Lubinski surprises the Russian advanced guard at Czyzew.--Marshal Diebitsch attacks the Polish rear-guard at Kleczkowo.--The rear-guard quits its position at night, and joins the main army at Ostrolenka.--Battle of Ostrolenka. Quitting the main army, which had thus successfully executed the important operation of driving the Russian imperial guard from the kingdom, and sending a corps into Lithuania,--we will now turn to take a view of the state of affairs in that province. The brave Lithuanians in a series of bloody encounters had made themselves severely felt by the enemy. In the departments of Roszyienie and Szawla, at about the middle of the month of May, a short time before the battle of Ostrolenka, the two Russian corps, under Malinowski and Szyrman, were almost annihilated by the Lithuanian insurgents, who, night and day, falling upon them from forest ambuscades, subjected them to immense losses. Those corps literally wandered about, for some time, and being unable to hold themselves in any position, were forced at last to evacuate Samogitia. In the department of Bialystok, the little corps recently sent under the command of general Chlapowski, began its operations with great success. In the environs of Bielsk, that small detachment, composed of four squadrons of the 1st regiment of lancers, consisting of four hundred and eighty horsemen, a hundred and ninety light infantry volunteers mounted,[58] and two pieces of cannon, routed two regiments of cossacks and two battalions of infantry, the latter being taken in a body and the former dispersed; and, what was of much importance to us, in Bielsk, as well as in Brainsk, several magazines of powder were found. In the environs of Bielsk, colonel Mikotin, aid-de-camp of the grand duke Michael, and on his way with despatches from him to the Grand Duke Constantine, was taken prisoner.[59] The corps of general Chlapowski left Bielsk in the direction of the town of Orla, and entered the forest of Bialowiek, where he received reinforcements of Lithuanian insurgents.