Seattle Mariners outfielder Greg Halman was stabbed to death Monday morning in the Dutch city of Rotterdam, local police said. The baseball player was 24. His 22-year-old brother was arrested and is being questioned. Halman, who was born in the Netherlands—in the city of Haarlem—played in Dutch leagues and was part of the gold-medal winning 2007 European championship squad. He appeared in 35 games for the Mariners last season and hit .230.