Sahih Muslim Book 53, Hadith 92
O Abu Jahl b. Hisham, O Umayya b. Khalaf, O Utba b. Rab'ila, O Shaiba b. Rabi'a, have you not found what your Lord had promised with you to be correct? As for me, I have found the promises of my Lord to be (perfectly) correct. Umar listened to the words of Allah's Apostle (ﷺ) and said: Allah's Messenger, how do they listen and respond to you? They are dead and their bodies have decayed. Thereupon he (the Holy Prophet) said: By Him in Whose Hand is my life, what I am saying to them, even you cannot hear more distinctly than they, but they lack the power to reply. Then'he commanded that they should be buried in the well of Badr.
We were along with Umar between Mecca and Medina that we began to look for the new moon. And I was a man with sharp eye- sight, so I could see it, but none except me saw it. I began to say to 'Umar: Don't you see it? But he would not see it. Thereupon Umar said: I would soon be able to see it (when it will shine more brightly). I lay upon bed. He then made a mention of the people of Badr to us and said: Allah's Messenger (ﷺ) showed us one day before (the actual battle) the place of death of the people (participating) in (the Battle) of Badr and he was saying: This would be the place of death of so and so tomorrow, if Allah wills. Umar said: By Him Who sent him with truth, they did not miss the places (of their death) which Allah's Messenger (ﷺ) had pointed for them. Then they were all thrown in a well one after another. Allah's Messenger (ﷺ) then went to them and said: O, so and so, the son of so and so; O so and so, the son of so and so, have you found correct what Allah and His Messenger had promised you? I have, however, found absolutely true what Allah had promised with me. Umar said: Allah's Messenger, how are you talking with the bodies without soul in them. Thereupon he said: You cannot hear more distinctly than (their hearing) of what I say, but with this exception that they have not power to make any reply.
When it was the Day of Badr and Allah's Apostle (ﷺ) had gained victory over them (the Meccans), he commanded more than twenty persons, and in another hadith these are counted as twenty-four persons, from the non-believers of the Quraish to be thrown into the well of Badr. The rest of the hadith is the same.