The Messenger of Allah ﷺ forbade picking up the lost property of a pilgrim. Harun, in his narration, mentioned Amr bin Harith. Abdullah said, "And I heard it myself from Harun."
قال حدثنا سريج وهارون قالا حدثنا ابن وهب عن عمرو بن الحارث عن بكير بن الأشج عن يحيى بن عبد الرحمن بن حاطب
أن رسول الله ﷺ نهى عن لقطة الحاج وقال هارون في حديثه عمرو بن الحارث قال عبد الله وسمعته أنا من هارون
No references are available.
Its isnad is sahih, its narrators are well known, and Yahya bin Abdul-Rahman bin Hatib bin Abu Baltaah is trustworthy, his hadith appears in Muslim and the Sunan works. Muslim narrated the hadith 3/1351, no. 1724, in the chapter on lost property, the lost property of the pilgrim. Abu Dawud narrated it similarly 2/139, no. 1719, and Ibn Hibban narrated it 284, no. 1172, in the chapter on transactions.