Jami` at-Tirmidhi 1036

Abdur-Rahman bin Ka'b bin Malik narrated that:Jabir bin Abdullah informed him that the Prophet had put two men together in one cloth from those who were killed at (the battle of) Uhud, then he said: "Which of them memorized the more of the Qur'an?" When one of them was indicated to him, he put him in the Lahd (first) and said: "I am a witness for those people on the Day of Judgment." And he ordered that they be buried in their blood, and that they not be prayed over, nor washed