I'm rereading my draft, and there is a part in the book where when the main character is helping others escape prison, she accidentally reveals herself to the prison guards who chase her down and kill one of the people she was trying to rescue.

Is this too brutal? I don't want my reader to hate the main character for indirectly killing someone, but should I keep it or scrap it? I do have a backup idea that could easily take the place of her revealing herself and instead have someone else do it and have my main character swoop in as the hero, but I'm not sure which version to do. 

Edit: Thanks to @M.A.Golding and @FeRD for pointing out that I should add  that the prisoners were wrongfully imprisoned.