[4] The borough of Praga, located right across the Vistula from Warsaw, was initially left in Polish hands, garrisoned by a small force of 600 men.

However, the following day the besiegers were assaulted from the back by a Polish division-sized sortie from the Modlin Fortress under Gen. Michał Sokolnicki.

[5] Overnight on 24 April the Polish force left Serock and crossed the Narew, reaching Radzymin before daylight.

Finally on 2 and 3 May the entire corps under Gen. Mohr was defeated at Ostrówek and its pontoon bridge across the river was destroyed, thwarting any further attempts to advance further east.

This gave Poles enough time to leave the Austrians locked in Warsaw to their fate and liberate much of Galicia without much opposition from the enemy.