Numbers 3:4
Nadab and Abihu, however, died in the presence of the LORD when they offered strange fire before the LORD in the Wilderness of Sinai. And since they had no sons, only Eleazar and Ithamar served as priests during the lifetime of their father Aaron.

Leviticus 10:1, 2
Now Aaron's sons Nadab and Abihu took their censers, put fire in them, placed incense on them, and offered unauthorized fire before the LORD, contrary to His command. . . .

1 Chronicles 24:1, 2
These were the divisions of the descendants of Aaron. The sons of Aaron were Nadab, Abihu, Eleazar, and Ithamar. . . .