Traced to Ka'b al-Ahbar (automatic guess): a report of earlier scriptures, not a hadith of the Prophet ﷺ.
في ولاية القحطاني تقتتل قضاعة بحمص وحمير، وعليها يومئذ رجل من كندة، فتقتله قضاعة وتعلق رأسه في شجرة في المسجد، فتغضب له حمير، فيقتتلون بينهم قتالا شديدا، حتى تهدم كل دار عند المسجد كي تتسع صفوفهم للقتال، فعند ذلك يكون الويل للشرقي من الغربي، وغير ذلك بحمص، فتكون أشقى قبائل اليمن بهم السكون، لأنهم جيرانهم
In the state of Al-Qahtani, an otter fights with chicks and donkeys, and on that day is a man from Kindah. An otter kills him and hangs his head from a tree in the mosque. The donkeys become angry with him, and they fight fiercely among themselves, until every house near the mosque is demolished so that their ranks can expand to fight. In that case, woe will come to the eastern from the western, and otherwise to Homs, and they will be the most miserable of the tribes in Yemen in terms of peace, because they are their neighbors.
أبو المغيرةابن عياشالمشيخةكعبautomatic reading, unverified