What is the fine-grained topic of the following text: Details of Masood’s lengthy criminal history have continued to emerge since Wednesday’s terrorist attack, and as Sky notes, fears are also growing he may have been groomed for extremism during his time in prison, with a childhood friend claiming the killer turned to Islam and changed his name to Khalid Masood after serving a jail term for assaulting someone with a knife. Only return the topic.
Masood's radicalization and criminal history leading to a terrorist attack