Police are investigating the death of a 21-year-old University of Wisconsin-Madison student who was found dead in her apartment as a homicide.

Brittany Sue Zimmerman, a junior from Marshfield who was majoring in medical microbiology and immunology, was found dead by her boyfriend in their apartment.

Authorities want university students and downtown residents of Madison, Wis., to take extra precautions about their safety until the investigation is complete. There are no suspects.

Chief Noble Wray of the Madison police department said he was concerned about the tragic set of circumstances, myFOXWausau reported.

Dean of Students Lori Berquam urged those on campus to take advantage of the safety resources available, including the 'Safewalk' and 'Saferide' programs.

Click here for more coverage from myFOXWausau.com.

Dane County Coroner John Stanley expects results from an autopsy soon.

If Zimmerman was murdered, it would be the city's second homicide this year. Madison authorities are investigating three unsolved murders.

Death of University of Wisconsin-Madison Student Spreads Fear

Police spokesman Joel DeSpain said a large number of detectives were called to the homicide scene, about five blocks from the state Capitol on West Doty Street.

He said officers initially responded to the apartment about 1 p.m.

Anyone who saw anything suspicious in the area was asked to call the Madison Area Crime Stoppers tip line at 608-266-6014.

The Associated Press contributed to this report.