The Prophet (peace and blessings of Allaah be upon him) turned towards the Muslims, and the first one who recognized him beneath his armour was Ka’b ibn Maalik, who shouted at the top of his voice, “O Muslims! Rejoice! This is the Messenger of Allaah (peace and blessings of Allaah be upon him)!” He gestured to him to be quiet, and the Muslims gathered around him . . . .

Zaad al-Ma’aad, 3/199

And Allaah knows best.

Islam Q&A

https://islamqa.info/en/20181