The University of Minnesota Duluth student fatally shot Tuesday is the son of a St. Paul police sergeant.
William Andrew Grahek, 22, died at the hospital after being shot at home on East 11th Street in Duluth around 2 p.m., the Duluth Police Department said Wednesday.
Police said Tuesday night they had detained a person of interest, but the next day said no one is in custody.
"This continues to be a very active investigation and we are following up on numerous leads," the department said.
Police Chief Mike Tusken told the Duluth News Tribune the preliminary investigation suggests the shooting may have been connected to a robbery or home invasion.
Grahek is the son of St. Paul Police Sgt. Jon Grahek, the St. Paul Police Department said in an emailed statement. He grew up in Centerville and graduated from Centennial High School, before enrolling at UMD. He was also a specialist with the 312th Army Reserve Engineer Company, based in Duluth.
"The Graheks do not wish to make a public statement other than to say that they loved William very much and to thank everyone who has reached out to them with comforting words and support," the department's statement said.
This was the sixth shooting in Duluth less than a month, but the only one that proved to be fatal, the Duluth News Tribune said.