The Assyrians soon returned to Egypt.
Together with Psamtik I's army, which comprised Carian mercenaries, they fought a pitched battle in north Memphis, close to the temple of Isis, between the Serapeum and Abusir.
Tantamani was defeated and fled to Upper Egypt but just 40 days after the battle, Ashurbanipal's army arrived in Thebes.
Tantamani had already left the city for Kipkipi, a location that remains uncertain but might be Kom Ombo, some 200 km (120 mi) south of Thebes.
The city itself was conquered "smashed (as if by) a floodstorm" and heavily plundered.
The event is not mentioned in Egyptian sources but is known from the Assyrian annals, which report that the inhabitants were deported.
The Assyrians took a large booty of gold, silver, precious stones, clothes, horses, fantastic animals, as well as two obelisks covered in electrum weighting 2.500 talents (c. 75.5 tons, or 166,500 lb):
"This city, the whole of it, I conquered it with the help of Ashur and Ishtar.
Silver, gold, precious stones, all the wealth of the palace, rich cloth, precious linen, great horses, supervising men and women, two obelisks of splendid electrum, weighing 2,500 talents, the doors of temples I tore from their bases and carried them off to Assyria.
With this weighty booty I left Thebes.
Against Egypt and Kush I have lifted my spear and shown my power.
With full hands I have returned to Nineveh, in good health."

— Rassam cylinder of Ashurbanipal
The sack of Thebes was a momentous event that reverberated throughout the Ancient Near East.
It is mentioned in the Book of Nahum chapter 3:8-10
Art thou better than populous No, that was situate among the rivers, that had the waters round about it, whose rampart was the sea, and her wall was from the sea?
Ethiopia and Egypt were her strength, and it was infinite; Put and Lubim were thy helpers.
Yet was she carried away, she went into captivity: her young children also were dashed in pieces at the top of all the streets: and they cast lots for her honourable men, and all her great men were bound in chains.

and a prophecy in the Book of Isaiah 20:3-5 refers to the sack as well
Just as my servant Isaiah has gone stripped and barefoot for three years, as a sign and portent against Egypt and Cush, so the king of Assyria will lead away stripped and barefoot the Egyptian captives and Cushite exiles, young and old, with buttocks bared—to Egypt’s shame.
Those who trusted in Cush and boasted in Egypt will be dismayed and put to shame.
The Assyrians soon returned to Egypt. Together with Psamtik I's army, which comprised Carian mercenaries, they fought a pitched battle in north Memphis, close to the temple of Isis, between the Serapeum and Abusir. Tantamani was defeated and fled to Upper Egypt but just 40 days after the battle, Ashurbanipal's army arrived in Thebes. Tantamani had already left the city for Kipkipi, a location that remains uncertain but might be Kom Ombo, some 200 km (120 mi) south of Thebes. The city itself was conquered "smashed (as if by) a floodstorm" and heavily plundered. The event is not mentioned in Egyptian sources but is known from the Assyrian annals, which report that the inhabitants were deported. The Assyrians took a large booty of gold, silver, precious stones, clothes, horses, fantastic animals, as well as two obelisks covered in electrum weighting 2.500 talents (c. 75.5 tons, or 166,500 lb):
"This city, the whole of it, I conquered it with the help of Ashur and Ishtar. Silver, gold, precious stones, all the wealth of the palace, rich cloth, precious linen, great horses, supervising men and women, two obelisks of splendid electrum, weighing 2,500 talents, the doors of temples I tore from their bases and carried them off to Assyria. With this weighty booty I left Thebes. Against Egypt and Kush I have lifted my spear and shown my power. With full hands I have returned to Nineveh, in good health."
— Rassam cylinder of Ashurbanipal
The sack of Thebes was a momentous event that reverberated throughout the Ancient Near East. It is mentioned in the Book of Nahum chapter 3:8-10
Art thou better than populous No, that was situate among the rivers, that had the waters round about it, whose rampart was the sea, and her wall was from the sea? Ethiopia and Egypt were her strength, and it was infinite; Put and Lubim were thy helpers. Yet was she carried away, she went into captivity: her young children also were dashed in pieces at the top of all the streets: and they cast lots for her honourable men, and all her great men were bound in chains.
and a prophecy in the Book of Isaiah 20:3-5 refers to the sack as well
Just as my servant Isaiah has gone stripped and barefoot for three years, as a sign and portent against Egypt and Cush, so the king of Assyria will lead away stripped and barefoot the Egyptian captives and Cushite exiles, young and old, with buttocks bared—to Egypt’s shame. Those who trusted in Cush and boasted in Egypt will be dismayed and put to shame.
Sack of Thebes