He commanded a considerable force, some 10,000 strong, and with this and his cannon he laid siege to the citadel.
The natural strength of the place was such as might have defied any attempt to reduce it by force; but victuals were running low, and there was every likelihood of its being speedily starved into surrender.

To frustrate this, Beaumont conceived the daring plan of attempting to send in supplies from Mendavia.

The attempt being made secretly, by night and under a strong escort, was entirely successful; but, in retreating, the Beaumontese were surprised in the dawn of that February morning by a troop of reinforcements coming to Cesare's camp.

These, at sight of the rebels, immediately gave the alarm.
The most hopeless confusion ensued in the town, where it was at once imagined that a surprise attack was being made upon the Royalists, and that they had to do with the entire rebel army.
Cesare, being aroused by the din and the blare of trumpets calling men to arms, sprang for his weapons, armed himself in haste, flung himself on a horse, and, without pausing so much as to issue a command to his waiting men-at-arms, rode headlong down the street to the Puerta del Sol.

Under the archway of the gate his horse stumbled and came down with him.