Sayyiduna al-Miqdad bin al-Aswad (may Allah be pleased with him) said: I said: "O Messenger of Allah, I met a man from the polytheists and he cut off my hand, then he took refuge from me behind a tree and said: 'I have submitted to Allah (become Muslim)'" - and he narrated the rest of the same hadith that has passed before.
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17729