Bismihi ta'ala
Imam Husain (a.s.), the grandson of the Prophet of Islam (s.a.w.) was beseiged in the plains of Karbala, Iraq, and innocently killed along with some of his family members and companions.
Should you wish to read further about this topic, please refer to these following links:
https://www.al-islam.org/library/imam-al-husayn-and-karbala
And:
https://whoishussain.org/who-is-hussain/the-full-story/
Wassalam