Surah Al-Baqarah 2:65

وَلَقَدْ عَلِمْتُمُ ٱلَّذِينَ ٱعْتَدَوْا۟ مِنكُمْ فِى ٱلسَّبْتِ فَقُلْنَا لَهُمْ كُونُوا۟ قِرَدَةً خَـٰسِـِٔينَ

And you had already known about those who transgressed among you concerning the sabbath, and We said to them, "Be apes, despised."

Translation: Saheeh International

Tafsir

And verily wa-la-qad the lām is for oaths you know that there were those among you who transgressed violated the Sabbath by fishing when We had forbidden you to do so — these were the inhabitants of Eilat — and We said to them ‘Be apes despised!’ rejected and they became so they died three days later.

Excerpt from Tafsir al-Jalalayn, commentary on 2:65, via Quran.com. The reader has the full commentary and 9 more tafsirs.