Jami` at-Tirmidhi 1549
جامع الترمذي#1549Da'ifNarrated Ibn 'Asim Al-Muzani:From his father and he was a Companion who said: "When the Messenger of Allah (ﷺ) dispatched any army or battalion, he would say to them: 'If you see a Masjid, or hear someone calling the Adhan, then do not kill anyone
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirDaif
Al-AlbaniDaif
Zubair Ali ZaiDaif
In-book reference: 21:2