Russian probes of Lithuanian border defenses began several hours before the formal invasion. These ranged from one or two infiltrators attempting to destroy telephone wires and brigades, up to battalion-sized incursions seeking to seize jump-off points for the main attack. Weeks of Russian bluster had taken some of the edge off Lithuanian preparedness, with the defenders expecting an attack on the Tsar's birthday, not almost two weeks early.

The Russians had built a well-trained, well-equipped army, but the Lithuanians felt themselves ready to face it. They found themselves badly outmatched and had to fall back from their forward positions. Retreating in the face of what was clearing a probing attack did not augur well for the country's defense, but before dawn broke the Lithuanian government had invoked the common defense clause of the Central Powers alliance. Help would be coming, if only the Iron Wolves could hold out.