Lakshmana had reached before Shurpanakha could harm Seeta. He tried to stop her, but she went mad in anger. To avenge her ridicule, she wanted to kill Seeta.
When Shurpanakha did not listen, Lakshmana grew furious and drew his sword. He attacked her, cutting off her ears and nose. Shurpanakha screamed with pain. Howling with pain, screaming abuse, and threatening revenge, Shurpanakha fled into the dense forest.

With bleeding ears and nose she reached her brothers, Khara and Dooshan. Seeing her awful condition they asked her the reason. She poured out her story. She told them that Rama and Lakshmana, the sons of king Dasharatha of Ayodhya, dressed like ascetics, had mutilated her by cutting off her ears and nose. “And all because of that insect who is Rama’s wife, Seeta! Kill them!” screamed Shurpanakha, “They are dwelling fearlessly in your domain. And you are whiling away your time.”
Khara immediately sent his fourteen demon generals under the command of Dooshana to kill the two men and drag the woman to his presence. Rama knew that the demons would surely come for revenge. So, he asked Lakshmana to take Seeta away to a cave for safety, while he himself dealt with the demon-army.

Rama’s bow shot arrows faster than lightning and soon all the demon-generals lay dead. When Dooshana attacked Rama, the prince cut off both his arms and the demon fell dead there and then. Trishira, the three-headed demon, came next, but Rama shot him dead with his serpent arrow. After the annihilation of the demon-army, Khara armed with weapons reached there in his chariot. Rama destroyed his chariot and all his weapons. Rama simply tore his chest apart with his sharp arrows. Shurpanakha hiding behind a tree saw the prowess of Rama. Lakshmana returned with Seeta and proudly embraced his brave brother who had destroyed Khara, Dooshana, Trishira and their army single-handedly.