| 1. Abu was born into a middle-class Bengali Hindu family. |
| 2. After meeting his Muslim wife, he converted to Islam and changed his name to “Abu Rumaysah al-Britani”. |
| 3. He became an active member of the banned al-Muhajiroun network and recruited followers outside mosques and online. |
| 4. While living in the UK, he resided in Walthamstow and worked as a salesman for a bouncy castle company. |
| 5. In 2014, he fled to Syria after skipping police bail in the UK. |
| 6. Abu became a senior ISIS commander after Jihadi John's death. |
| 7. He carried out executions of western hostages in ISIS propaganda. |
| 8. He authored a book titled “A Brief Guide to Islamic State” in 2015. |
| 9. In January 2018, the U.S. designated him as a global terrorist and imposed sanctions. |
| 10. Following his conversion in his late teens, he took the name Saiful Islam (Abu Rumaysah is a "kunya", or nickname, which means "Father of Rumaysah"). |
| 11. In September 2014, he fled to Syria after skipping police bail while under investigation for allegedly encouraging terrorism. He boarded a coach for Paris with his wife and children, despite being banned from travelling and ordered to hand in his passport. |
| 12. Weeks after arriving in Syria, he posted an image online of himself holding a rifle and his newborn fourth child, tweeting: "What a shoddy security system Britain must have to allow me to breeze through Europe to [IS]." |
| 13. He authored a "Lonely Planet-style" travel booklet titled “A Brief Guide to Islamic State” in 2015, encouraging others to emigrate to the Islamic State. |
| 14. He was a prominent follower of hate preacher Anjem Choudary. |
| 15. He was converted to Islam by childhood friend Mohammed Mizanur Rahman, who also radicalized him through al-Muhajiroun. |
| 16. In 2014, he was under investigation by British authorities for allegedly encouraging terrorism but disappeared after being released on bail. |
| 17. In September 2014, he fled to Syria with his wife Aisha Tariq and their four children, departing from Victoria Coach Station in London for Paris despite being banned from travelling. |
| 18. He carried out executions of prisoners accused of spying for the United Kingdom in ISIS propaganda videos. |
| 19. In January 2016, he appeared in an ISIS propaganda video in which he called British Prime Minister David Cameron an imbecile before executing five prisoners. |
| 20. British media labeled him 'Jihadi Sid' following the January 2016 execution video. |
| 21. He was a prominent follower and associate of hate preacher Anjem Choudary. |
| 22. He used social media to promote Islamist views and attended demonstrations in Britain against the United States, Israel, and Arab governments. |
