📖Valmiki Ramayana Chapter 76
Hearing the words of Rama of imperishable exploits, that ascetic, his head still hanging downwards, answered – “O Rama, I was born of a Shudra alliance and I am performing this rigorous penance in order to acquire the status of a God in this body. I am not telling a lie, O Rama, I wish to attain the Celestial Region. Know that I am a Shudra and my name is Shambuka. As he was yet speaking, Raghava, drawing his brilliant and stainless sword from its scabbard, cut off his head. The Shudra being slain, all the Gods and their leaders with Agni’s followers, cried out, “Well done! Well done!” overwhelming Rama with praise, and a rain of celestial flowers of divine fragrance fell on all sides, scattered by Vayu. In their supreme satisfaction, the Gods said to that hero, Rama.
Rama killed a Shudra & all the gods were afraid because of Shambuka meditation and knowledge and Shambuka was a low caste Hindu so Rama killed him and all the gods praised Rama.
Reference Valmiki Ramayana Chapter 76