On December 23, 1842, Fisher and some of the men crossed the Rio Grande and entered Mier, where they met no resistance. They demanded supplies from the town, which the town's alcalde delivered. The troops withdrew and waited. In the meantime, a large detachment of Mexican troops arrived in the town.

On December 25, the two sides engaged in a bloody battle that lasted almost day. The Texans sustained thirty casualties and ran out of food, water, and ammunition. More than 200 Texans surrendered to Mexican forces, unaware that they had mauled the Mexican troops to an almost unbelievable degree, inflicting an astounding 800 casualties.

159 white beans and 17 black beans