(CBS) — The former Northwestern University professor and a University of Oxford employee charged with fatally stabbing a hair stylist in River North arrived back in Chicago overnight to face murder charges.

Wyndham Lathem, 42, and 56-year-old Andrew Warren are accused of the July 27 stabbing death of 26-year-old Trenton James Cornell-Duranleau, at Lathem’s apartment in the 500 block of North State Street.

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The suspects were the subject of a national manhunt before they turned themselves in to authorities in California’s Bay Area Aug. 4.

A Chicago police extradition team travelled to California. Warren arrived at Area South Headquarters around 11:30 p.m. Friday, and Lathem arrived in a separate vehicle just before 1 a.m. Saturday. The two could make court appearances here as early as early next week, police said.

Lathem was an associate professor of microbiology and immunology at Northwestern, while Warren was an employee of Somerville College, in the Oxford system, in Great Britain.

Police have said officers were called to Lathem’s building on July 27 to conduct a well-being check after an anonymous caller reported a possible crime in the professor’s 10th floor apartment.

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Officers found a “very gruesome” crime scene inside, with the victim “savagely murdered,” Chicago Police Department spokesperson Anthony Guglielmi has said.

Lathem and Warren allegedly traveled to Lake Geneva, Wisc., after the murder and made a $1,000 donation to the Lake Geneva Public Library in the victim’s name after committing the murder, according to Guglielmi. Lathem also reportedly sent a video to friends and family members apologizing. Northwestern University fired him after a murder warrant was issued.

Chicago Police believe there was a romantic “relationship” between Lathem and Duranleau, a hair stylist, and that “something went terribly wrong,” Guglielmi said.

Police want to know why Warren, who arrived in the U.S. roughly 36 hours before the murder, came to this country and how and why he ended up connecting with Lathem.

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