Authorities in Chicago say a prominent medical scholar from Northwestern University and a British payroll clerk employed by Oxford who are accused of savagely killing a hairstylist last week before fleeing the city have been taken into custody in California.

Wyndham Lathem, 42, and Andrew Warren, 56, are suspects in the stabbing death of Trenton Cornell-Duranleau, 26, whose body was discovered by police July 27 inside Lathem’s luxury apartment in the city’s affluent River North neighborhood. The attack was so vicious, police say, that it left the knife blade shattered.

Warren surrendered to police in San Francisco, Calif. and Lathem turned himself in at Oakland federal building, according to the Associated Press. Their surrender was “negotiated,” Michael McCloud, fugitive taskforce commander with the U.S. Marshals Service, told the AP, without providing details.

Chicago police say the two men will appear before an Oakland Court before being returned to Chicago, where they will be interrogated by homicide detectives.

“Both individuals will be held accountable for their actions and we hope today’s arrest brings some comfort for the victim’s family. We are also thankful that this did not end in further tragedy,” Chicago police said in a statement.

The case has attracted international attention, with both suspects working for prestigious universities yet having no clear connection to one another or the victim.

Earlier Friday, Chicago police disclosed that a video has surfaced in which Lathem apparently apologized to friends and family for his alleged involvement in Cornell-Duranleau’s death. Officials declined to release the footage, saying it’s “integral to any future interrogation efforts.”

Lathem is an associate professor at Northwestern University and a sought-after speaker for his research on bubonic plague.

Warren, whose family in England reported him missing just days before the alleged murder, works for the University of Oxford processing paychecks and pensions. It’s unclear how the three men knew one another, apart from a Facebook connection between Lathem and Cornell-Duranleau, and authorities have not disclosed any motive except to say the attack may be tied to a domestic incident.

Citing friends in Britain, the Telegraph reported Thursday that Warren traveled to the United States without telling his boyfriend or any of his family, who have since appealed for him to surrender. They described Warren as reclusive, shy and consumed by grief since his father’s sudden death last winter.

“We have always known him as straight up and squeaky clean as regards the law,” one acquaintance told the Telegraph.

Chicago faces one of its most violent periods in 20 years. America’s third-largest city is on pace to exceed 700 homicides for the second straight year, according to a recent analysis by the Chicago Tribune.

Reports suggest that Warren may have been staying with Lathem in the Grand Plaza Apartments, a luxury building with plum amenities and stunning views of the surrounding city skyline. Monthly rents for some units there exceed $3,300.

Lathem has taught microbiology and immunology since 2007 at Northwestern’s Feinburg School of Medicine. A former colleague described him as competitive in seeking funding for his work from the National Institutes of Health and respected for the quality of his research.

Lathem is on administrative leave and is banned from entering campus facilities, school officials said. His public profile was scrubbed from the university’s website.

“I had him give a talk to some students about his research,” Menan Mehta, a Feinberg medical student, told ABC 7. “He just seemed like a perfectly normal guy.”

Cornell-Duranleau, who went by Trent, moved to Chicago only recently and lived in the city’s Pilsen neighborhood, about a 30-minute drive from Lathem’s apartment in River North. He was from Corunna, Mich., according to his Facebook profile. The city of 3,400 is just west of Flint. He later moved to the Detroit area.

“We were just shocked when we found this out. Even the clients,” said a former colleague at Timber’s Salon in Trenton, Mich., where Cornell-Duranleau worked as a stylist for several months.

The former colleague, who did not wish to be identified, told The Washington Post that Cornell-Duranleau loved his career in cosmetology. She described him as affable and generous, “always willing to help anybody.”

His mother, Charlotte Cornell, issued a statement Thursday asking for privacy as the investigation continues. She told the Associated Press that the family does not know the suspects, although she declined to say whether her son had ever talked about either them.

This post has been updated.

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