From Sahih Muslim (Hadith 3751):
Sa'id b. Jubair reported that Mus'ab b. Zubair did not effect separation between the Mutala'inain (invokers of curses). Sa'id said:It was mentioned to 'Abdullah b. Umar (Allah be pleased with them) and he said: Allah's Apostle (ﷺ) effected separation between the two members of Banu al-'Ajlan
Reference: Muslim 3751