Estero Bellaco

After two weeks on Paraguayan soil, the Allies haven't seen much action. López troops moved inland, waiting for a chance to drive Mitre's men out of the Paraguayan territory.The Allied Forces moved carefully northward to a place called Estero Bellaco, a swamp mud terrain covered with palms. Since that time the problems of relationship between Mitre and the Brazilian commanders were present.

Many officers of the Imperial Army were discontent that the command of the Allied Army was given to an Argentinean. Brazilian troops fulfilled two-thirds of the combined army. Particularly, the Brazilian officers found themselves better trained than his Allies counterpart. Now, they were displeased by Mitre's conduct of operations. They felt that the Allied Force should be more offensive. The two weeks of caution and slow advance was intolerable for them. The major problem of the two opponents was how to estimate the enemy's forces. Mitre, however, had another one. He had no idea of the kind of terrain ahead of his troops. Therefore, he preferred to be cautious.

Nevertheless, he would not have to wait long for action.

On May 2, 1866, 3.500 Paraguayan Troops, under Colonel José Díaz, launched an attack on the Allie's vanguard under General Venâncio Flores, leader of the Colorado Party and now president of Uruguay. He  was in command of three Uruguayan Battalions on the head of the Allied position. The attack was a complete surprise for him and his men. Besides, the attacking force outnumbered them. Flore's soldiers fought with great tenacity against Díaz' men, but they could not avoid the loss of a battery of four La Hitte cannons. Soon Flores had to undertake a retreat. This maneuver was embarrassed by a pool and the flooded terrain that lay between their position and the army under Mitre. Díaz pursued the Uruguayan troops, maybe trying to capture a great number of prisoners. Unfortunately, for him, the shots and the fight put the Allied Army aware of the situation. In a glance, the situation had changed. Now Diaz was fighting the bulk of the enemy army. Only with fierce determination he and his men escaped back to the Paraguayan encampment.

The Allies suffered 1.600 casualties. The 38th Infantry Battalion of the Brazilian Army, that came in Flores aid, had 94 dead and 188 wounded. The casualties of the 1st Cavalry Regiment of the Argentinean Army summed up to one hundred men. Flores Florida Battalion lost 19 of its 27 officers.

Colonel Diaz Paraguayan Army archives

The Paraguayan' losses mounted up to a number between 2.000 and 2.300, but they had captured a battery of cannons.

While Diaz and the Allies where fighting in Estero Bellaco, Lopez was waiting for news about the battle. He was planning to defeat the enemy with a quick blow on Tuyuty, where he believed his army would be able to achieve a great victory.

The Imperial Navy on  Paraná River (1866) - Brazilian Navy archives

Tuyuty