Ja'far AS was killed
Al-Kāfi|Volume 8|Book 1|Chapter 564
أَبَانٌ عَنْ أَبِي بَصِيرٍ عَنْ أَبِي عَبْدِ اللَّهِ (عليه السلام) قَالَ بَيْنَا رَسُولُ اللَّهِ (صلى الله عليه وآله) فِي الْمَسْجِدِ إِذْ خُفِضَ لَهُ كُلُّ رَفِيعٍ وَ رُفِعَ لَهُ كُلُّ خَفِيضٍ حَتَّى نَظَرَ إِلَى جَعْفَرٍ (عليه السلام) يُقَاتِلُ الْكُفَّارَ قَالَ فَقُتِلَ فَقَالَ رَسُولُ اللَّهِ (صلى الله عليه وآله) قُتِلَ جَعْفَرٌ وَ أَخَذَهُ الْمَغْصُ فِي بَطْنِهِ.
565. Aban, from Abu Baseer, who said the following: Abu Abdullah عليه الصلاة والسلام has said: ‘Once the Rasool Allah صلى الله عليه وعلى آله وسلم was in the Masjid, when every high thing was lowered for him صلى الله عليه وعلى آله وسلم and every low thing was raised for him صلى الله عليه وعلى آله وسلم, to the extent that he صلى الله عليه وعلى آله وسلم saw Ja’far عليه السلام fighting the infidels. He عليه السلام got killed. So the Messenger صلى الله عليه وعلى آله وسلم said: ‘Ja’far has been killed’, and a severe pain struck him عليه السلام in his صلى الله عليه وعلى آله وسلم stomach’.
- Mirʾāt al-ʿUqūl fī Sharḥ Akhbār Āl al-Rasūl (16/563)
- Ṣaḥīḥ al-Kāfī, vol. 3, p. 408