Apart from Jewish people who else was sent to the concentration camps and what happened to them?

Of the roughly 11 million killed during the Nazi Holocaust, nearly half were non-Jews. These included groups considered racially undesirable such as Gypsies, Ukrainians, Belorussians, Poles, etc., and also included Jehovah's Witnesses, homosexuals, clergy, communists, socialists, and other political enemies. Additionally, many non-Jews were persecuted because they were thought to be Jews, and of course, those caught trying to protect or hide Jews were killed as well.

Answer: The Nazis persecuted homosexuals, gypsies, and handicapped. They even killed many of the criminals in Nazi Germany.