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At least 19 people were killed and 50 injured Monday night in a suspected terrorist attack at an arena in Manchester, England, police said.

Singer Ariana Grande had just finished performing at the Manchester Arena when there was "a loud bang," concertgoer Erin McDougle told The Guardian. "The lights were already on, so we knew it wasn't part of the show." British Transport Police said it appears that an explosion hit the building's foyer at around 10:30 p.m., while the Manchester Arena said it happened "outside the venue in a public space."

This is a breaking news story and has been updated throughout.