A Northwestern University Professor and a University of Oxford employee surrendered Friday after a warrant was issued for their arrests in connection to the murder of a 26-year-old man. Wyndham Lathem, an associate professor of microbiology and immunology at Northwestern in Chicago, and Andrew Warren, an administrative assistant at Oxford in England, ended the manhunt when they gave themselves up in Northern California.

Lathem, 42, allowed himself to be arrested Friday outside a federal building in Oakland. Warren, 56, entered a police station in San Francisco and gave himself up the same day. Arrest warrants for both men were issued Wednesday for first-degree murder in the death of Trenton Cornell-Dunleau. Cornell-Dunleau, 26, was found viciously stabbed to death inside a Chicago apartment building July 27.

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In a court hearing Monday, Lathem could be seen smiling, waving and blowing kisses at people, according to the Associated Press. Lathem waived extradition and was set to return to Illinois. Neither man had yet been officially charged with a crime, though Lathem’s attorney said he would plead not guilty to murder when charged.

Lathem had reportedly been in a relationship with Cornell-Duranleau at the time of his death, police said. Cornell-Duranleau had been stabbed so severely the blade broke off the knife, according to reports. Lathem and Warren were seen on surveillance video leaving the apartment building the day of the attack.

“We have many, many unanswered questions,” Anthony Guglielmi, a spokesman for the Chicago Police Department, told the New York Times Monday. “We have ideas about what has taken place and the physical evidence, but we have a little bit more follow-up working to do.”

Adding mystery to the crime was the bizarre behavior of Lathem in the days after the crime took place. Investigators were confused by a $1,000 donation made in the victim’s name at a library in Wisconsin. In addition, Lathem sent a video to friends and family in which he referred to “the biggest mistake of his life.”

It emerged Monday that Lathem had begun preparing to move to France to work at the Institut Pasteur but his plans were crushed after he was denied the security clearance necessary to work with pathogens. His application was subsequently turned down.

“Wyndham Lathem did not receive security clearance from the French authorities,” Aurelie Perthuison, a spokesperson for the institute, told the Chicago Tribune. “This clearance being essential for this type of position, the recruitment was not pursued.”

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When the two men surrendered Friday, federal agents said Lathem appeared exhausted and unshaven.

“He looked a little disheveled,” Michael McCloud, a fugitive task force commander with the United States Marshals Service, told the Chicago Tribune. “Like he hadn’t slept much the last couple of days, but at the same time there was a look relief. Relief because of stress, of being on the run for a week.”

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