On 26 July, Cassan's garrison heard the distant sounds of battle to the northeast in the direction of Roncevaux Pass. The noise came from a skirmish fought between Clausel's corps and Lowry Cole's 4th Division at Lizoáin. The next day, Thomas Picton's 3rd Division and Pablo Morillo's Spanish division began occupying positions near the city, indicating that French forces might be nearby. O'Donnell's Spanish division on the south side of Pamplona marched away to join the other Allies in the afternoon. There was a brief opportunity for Cassan to march his garrison through the gap and escape to the east. However, he wanted to be in control of the city when Soult's relief army broke through, so the chance passed.