Muhammad ibn Jarir al-Tabari describes the assassination thus:
When they got to Khaybar they went to Sallam’s house by night, having locked every door in the settlement on the inhabitants. Now he was in an upper chamber of his to which a ladder led up. They mounted this until they came to the door and asked to be allowed to come in. His wife came out and asked who they were and they told her that they were Arabs in search of supplies. She told them that their man was here and that they could come in. When we entered we bolted the door of the room on her and ourselves fearing lest something should come between us and him. His wife shrieked and warned him of us, so we ran at him with our swords as he was on his bed . . . . When we had smitten him with our swords Abdullah bin Unays bore down with his sword into his belly until it went right through him.
Abu Rafi's assassination is mentioned in many Sunni Hadith:
Narrated Al-Bara bin Azib: Allah's Apostle sent a group of Ansari men to kill Abu-Rafi. One of them set out and entered their (i.e. the enemies) fort. That man said, "I hid myself in a stable for their animals. They closed the fort gate. Later they....."Sahih al-Bukhari, 4:52:264