The Prophet sent seventy men from the tribe of Bani Salim to the tribe...

Hadith 4:57

Narrated Anas:

The Prophet sent seventy men from the tribe of Bani Salim to the tribe of Bani Amir. When they reached there, my maternal uncle said to them, "I will go ahead of you, and if they allow me to convey the message of Allah's Apostle (it will be all right); otherwise you will remain close to me." So he went ahead of them and the pagans granted him security But while he was reporting the message of the Prophet , they beckoned to one of their men who stabbed him to death. My maternal uncle said, "Allah is Greater! By the Lord of the Kaba, I am successful." After that they attached the rest of the party and killed them all except a lame man who went up to the top of the mountain. (Hammam, a sub-narrator said, "I think another man was saved along with him)." Gabriel informed the Prophet that they (i.e the martyrs) met their Lord, and He was pleased with them and made them pleased. We used to recite, "Inform our people that we have met our Lord, He is pleased with us and He has made us pleased " Later on this Quranic Verse was cancelled. The Prophet invoked Allah for forty days to curse the murderers from the tribe of Ral, Dhakwan, Bani Lihyan and Bam Usaiya who disobeyed Allah and his Apostle