The Northwestern professor wanted in connection with a fatal stabbing in Chicago's River North neighborhood sent a video message to family members and friends after the killing, police said.
In the video, Professor Wyndham Lathem allegedly apologizes for his involvement in the murder of Trenton Cornell-Duranleau, according to authorities.
Police did not release the footage, saying it was "integral to any future interrogation efforts," but law enforcement sources said there was no mention of suicide in the message.
Arrest warrants have been issued for Lathem, 42, and Andrew Warren, 56, in connection with the killing of 26-year-old Cornell-Duranleau, who was found stabbed to death last week on the tenth floor of the Grand Plaza Apartments on State Street.
Chicago police spokesman Anthony Guglielmi said Friday the people who received the video have been interviewed by U.S. Marshals.
"We do have an idea of their whereabouts, and efforts to locate them are only intensifying from here on in," Guglielmi said in a Thursday statement.
He later confirmed to NBC 5 the men drove to Lake Geneva after the killing and donated $1,000 to the Lake Geneva Public Library in the victim's name.
"Our primary focus is to facilitate a safe surrender, and we strongly encourage Professor Lathem and Mr. Warren to do the right thing and turn themselves into any police department in the U.S. or contact CPD and we will make any necessary accommodations," Guglielmi said.
Police have said the men are believed to be "armed and dangerous" and may have fled from the Chicago area. Lathem's passport has been flagged and Warren's travel visa has been revoked, and the U.S. Marshal Service has also joined in the search.
Guglielmi added that the River North crime scene was "gruesome and the victim was savagely murdered."
He would not release further details on the crime scene, but the Chicago Tribune reported that blood was found on a bedroom door in the apartment where Cornell-Duranleau was found dead from stab wounds. The report, citing law enforcement sources, also said a knife with a broken blade was found in the trash in the kitchen, and another knife was located near the sink.
The pair of suspects was spotted on surveillance video leaving the property after the incident, authorities said.
Sources told the Tribune "blood was everywhere."
Cornell-Duranleau, a Michigan native and hairstylist, was pronounced dead at the scene just after 9 p.m. Thursday. An autopsy found he died of multiple sharp force injuries, and his death was ruled a homicide.
Lathem is an associate professor of microbiology and immunology at Northwestern University's medical school, where he has worked for 10 years. He has been placed on administrative leave and banned from entering Northwestern campuses, according to university spokesman Alan Cubbage.
“There is no indication of any risk to the Northwestern community from this individual at this time,” Cubbage said in an emailed statement.
Warren is a senior treasury assistant at the University of Oxford in Great Britain, according to the university’s website.
Both men disappeared after the young hairstylist was found dead, authorities said.
Residents were notified via email that Chicago police swept the property and were investigating motives in the killing, including whether it may have been a "domestic incident."