Numbers 26:10 in the World English Bible
and the earth opened its mouth, and swallowed them up together with Korah when that company died; at the time the fire devoured two hundred fifty men, and they became a sign.
Context
9 And the sons of Eliab; Nemuel, and Dathan, and Abiram. This is that Dathan and Abiram, which were famous in the congregation, who strove against Moses and against Aaron in the company of Korah, when they strove against the LORD:
10 And the earth opened her mouth, and swallowed them up together with Korah, when that company died, what time the fire devoured two hundred and fifty men: and they became a sign.
11 Notwithstanding the children of Korah died not.