‏البر والصلة والآداب‏ : Hadeeth No:6283 Umm Darda' reported on the authority of Abu Darda' as saying: I heard Allaah's Messenger (sallAllaahu alayhi wa sallam) as saying: The invoker of curse would neither be witness nor intercessor on the Day of Resurrection....

‏فضائل الصحابة‏ : Hadeeth No:6117 Khufaf b. Jura' reported that Allaah's Messenger (sallAllaahu alayhi wa sallam) said in prayer: O Allaah, hurl curse upon the tribe of Lihyan and Ri'l aid Dhakwan and Usayya for they disobeyed Allaah and His Messenger, (and for) Ghifar Allaah has granted pardon and for the tribe of Aslam Allaah has ...