An Oxford University employee will be returned to Chicago for questioning alongside a US professor on suspicion of murdering a 26-year-old hair stylist found with more than 40 stab wounds.
Somerville College's Andrew Warren, 56, and Professor Wyndham Lathem, 42, are accused of killing Trenton Cornell-Duranleau in the academic's Chicago apartment.
Warren declined to fight extradition when he appeared in court on Friday in San Francisco, where he surrendered himself after eight days as a fugitive during which the suspects travelled more than 2,000 miles across the States.
The Briton's appearance came as Chicago Police spokesman Anthony Guglielmi revealed the number of wounds inflicted to the upper body of the victim, who he said was experiencing tensions with Lathem.
"We have a lot of questions for Mr Lathem and Mr Warren and we look forward to their return to Chicago," Mr Guglielmi said.
"We have information to suggest there was tension in the relationship between Dr Lathem and the victim."
The Briton, appearing in a baggy, orange prison-issued sweatshirt and jogging bottoms, was denied bail and will be held in custody.
Judge Edward Torpoco said: "Based on the nature of the charge, the defendant is remanded and no bail is set."
Unshaven Warren timidly shuffled into the room in San Francisco's Hall of Justice while being filmed and photographed by the press.
Listening to the judge's procedural questions assisted by a hearing aid, he also quietly confirmed he is the wanted man and said he would accept a public lawyer on the basis he could not afford his own.
The judge permitted filming on the basis he had already been subject to extensive publicity as the subject of an eight-day manhunt.
After the hearing, his lawyer, Ariel Boyce-Smith, said: "Mr Warren is agreeable to being transported to Chicago, he wants the process to be started.
"I just want to remind everyone that he is presumed innocent and his agreement to go there to start the process is where we are now."
Warren and Lathem gave themselves up separately but at similar times in California on August 4.
Warren, who says online he lives in Swindon, Wiltshire, has since been suspended from his job as senior treasury assistant.
He had been reported missing to Thames Valley Police two days before the body was found, having left the UK on July 24.
The Chicago force said the body of Mr Cornell-Duranleau, originally from Corunna, Michigan, was found mutilated in a "very violent scene" on July 27.
Microbiologist Lathem, since sacked by Northwestern University, plans to plead not guilty, according to his lawyer Kenneth Wine who described him as a "gentle soul".
Neither of the suspects have been formally charged.