Police were called to a house where they found Halman bleeding from a stab wound, Rotterdam Police spokeswoman Patricia Wessels said. Paramedics were unable to resuscitate the young Dutch player.
Halman’s 22-year-old brother was arrested as a suspect. His name was not released to the public and so far no charges have been filed.
“He is under arrest and right now he is being questioned,” Wessels told the Associated Press in a phone interview. “It will take some time to figure out what happened.
After his June call-up to the majors, Halman his .230 in 35 games with a pair of home runs and six RBI. He hit 33 home runs in 2010 at Class AAA Tacoma.
Halman was the MVP of the Dutch league in 2004 and helped the Netherlands to the 2007 European Championship. He was the lone Dutch-born player in the majors last season and the first fully domestically developed major leaguer.
A 6-4, 210-pound power-hitting prospect, Halman was well-liked by many, as evidenced by the flood of shock and well-wishes from major leagues on Twitter.