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An attack this week in London just outside the British Parliament left five people dead and over 40 injured. The man behind that attack - one of those five dead - was a British-born Muslim convert according to the police. Since the attack, authorities have focused their investigation on the city in England where he recently lived, Birmingham. NPR's Frank Langfitt reports it's a city with a reputation as a hotspot for Islamic extremism.
FRANK LANGFITT, BYLINE: Khalid Masood spent a number of years living in this neighborhood in Birmingham. I'm actually looking at his house. It's a three-story red brick townhouse, and it's a nice neighborhood - looks relatively prosperous. I was just actually talking to a Chinese guy who drives a BMW, is in import-export - a woman here who's a university student.
KAODI CAMPELL: I've knocked his door for help, and he's come out and help me jump start my car. And his wife's answered the door. And, like, one minute, I'll get my husband - and just normal, really - normal family.
LANGFITT: Kaodi Campell lived across the street from the Masoods for several years. She described them as a cordial, observant Muslim family who were private and had few visitors.
When did he leave?
CAMPELL: Probably, like, December times. She would always dress, like, in the religious clothing (unintelligible).
LANGFITT: Any political conversations?
CAMPELL: Nothing like that. Even - nothing came across extremist to me.
LANGFITT: Like others here, Campell's trying to square her helpful neighbor with the man who launched the attack 120 miles southeast of here in London.
CAMPELL: Obviously these things was going around in his head.
LANGFITT: When Emma Webb heard Masood had lived in these parts...
EMMA WEBB: It wasn't particularly surprising in the sense that we know Birmingham and the West Midlands is the second hot spot in the United Kingdom after London.
LANGFITT: Webb is a research fellow at the Henry Jackson Society, a London-based think tank. The Society recently released a survey of Islamist terrorism in the U.K. between 1998 and 2015. It found nearly one-fifth of the cases involve people from this part of the country. Webb spoke over Skype.
WEBB: Birmingham actually has a very long history of extremism. Going all the way back to the 1990s, there were militant Kashmiri networks operating in that area. And we also know, for example, that we had the Trojan horse scandal where extremists attempted to take over schools in Birmingham.
LANGFITT: Police have released scan information about Masood. Although he had an extensive criminal past, it's not clear whether he was connected to Islamists here, but that will certainly be one focus of the investigation. His conversion to Islam could be another. Again, Emma Webb...
WEBB: The sort of common perception I suppose is that a convert is more likely to be zealous in trying to sort of prove their religiosity. And there are suggestions that extremists and extremist groups target these individuals.
LANGFITT: For many in Birmingham who call themselves Brummies, this week's attack in London was not only horrifying. It also felt like another black eye. Shabana Mahmood is a member of Parliament from Birmingham.
SHABANA MAHMOOD: As a Brummie, I think I just, you know, just feel a sense of horror that, you know, somebody else who might be connected to my wonderful city might be responsible in the preparation of this act or, in the case of Masood, be a resident of our city.
LANGFITT: Parliamentarian Mahmood notes that the city has 234,000 Muslims and emphasizes that only a tiny percentage have been involved in such attacks. Frank Langfitt, NPR News, Birmingham. Transcript provided by NPR, Copyright NPR.