Genesis 34:26
And they slew Hamor and Shechem his son with the edge of the sword, and took Dinah out of Shechem’s house, and went out. And they slew Hamor and Shechem his son with the edge of the sword, and took Dinah out of Shechem’s house, and went out.
The verse records Simeon and Levi killing Hamor and Shechem his son with the edge of the sword and taking Dinah out of Shechem's house, completing their ruinous destruction of the city. The attack was a deceitful, cruel, bloody and revengeful retaliation, though not unprovoked, and was a grievous sin, part of the cruelty Jacob knew his sons had practiced against the people of Shechem. God did not sanction their conduct.
The sons were not all righteous but were tainted with idolatry. Jacob did not know their purpose beforehand but learned of it only after the cruelty was done, to his horror. He reproved them for troubling him and making him despised among the inhabitants of the land, fearing the indignation of the surrounding nations would bring danger and destruction on him and his house, and in that distress he called upon God.
Jacob later condemned their fierce anger and cruel wrath, declaring they would be divided and scattered in Israel. Levi's later faithfulness to God changed that curse into a blessing through service at the sanctuary.