(Reuters) – A white teenager dressed in camouflage and body armor opened fire on Saturday in a grocery store in a Black neighborhood of Buffalo, New York, killing 10 people in an attack authorities are calling an act of “violent extremism” motivated by race. Authorities say the white man drove about 200 miles (320 km)from his home outside Binghamton to the store where he staged the apparently random attack and live-streamed the carnage on the social media platform Twitch. The rampage is the latest in a string of high-profile mass shootings in the United States this year, the second in the stat…