Sayyiduna Abdullah bin Amr (may Allah be pleased with him) said: I heard the Prophet (peace and blessings be upon him) say: "The one who kills Ammar and the one who takes his belongings will go to Hell."
Al-Tabarani recorded it; its chain contains Muslim al-Mula'i, who is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب المناقب / 15620