Police say that 19 people have been killed and another 50 injured after an explosion at the Manchester Arena in northern England, where U.S. pop star Ariana Grande was giving a concert. / O6 `# {4 g9 _; [8 C" j2 A4 J& ^; G+ T! j! k$ M( i2 \4 Z
They say they are treating it as a "terrorist incident" as they investigate.