The Aztecs recaptured their city with Cortés's men fleeing the city, followed by arrows and rocks. Some found their way to a causeway out of the city. Some others, like the troops of Juan Velázquez, were forced to retreat toward the center of the city, where they were captured and sacrificed. When night fell, Aztec attacks on the Spaniards eased. Cortés took advantage of this to cross the causeway to a place called Popotla. Here is still found an "ahuehuete" tree called the "Tree of the Sad Night" because Cortés supposedly wept here after his defeat. At least 600 of the Spanish were killed (some estimates state over 1,000), many weighed down by the gold they were carrying; several thousand Tlaxcalans were probably lost, too. At Tlaxcala, Cortés pacified his Indian allies and rebuilt his military force. The Aztecs thought the Spaniards were permanently gone. They elected a new king, Cuauhtemoc. He was in his mid-20s, the son of Moctezuma's uncle, Ahuitzotl, and was an experienced leader. After regrouping in Tlaxcala, Cortés decided to lay siege to Tenochtitlan in May 1521. For three months, the city suffered from the lack of food and water as well as the spread of disease brought by the Europeans. Cortés and his allies landed their forces in the south of the island and fought their way through the city, street by street, and house by house. The Spanish pushed the defenders to the northern tip of the island. Finally, Cuauhtemoc had to surrender in August 1521. With Tenochtitlan in ruins, the victorious Cortés first settled himself in Coyoacán on the lake shore at the southern edge of Lake Texcoco. He created the ayuntamiento or town council of the Spanish capital there, so that he could choose where the city would finally be. No one but Cortés wanted to rebuild the Aztec site. Most of the other conquistadors wanted the new city to be closer to the mountains, pastures and groves they would need for supplies, for example in Tacuba or in Coyoacán. Some accounts state that the Aztec islet was chosen because its location was strategic, allowing for rapid communication by boat to communities on the shorelines. However, the decision was Cortés's alone.