A Senegalese immigrant with a police record for drug dealing has confessed to the murder of American artist Ashley Ann Olsen, who was found naked and strangled in her apartment in Florence, Italy, last Saturday.

The 25-year-old suspect came to the attention of investigators from witness testimony combined with evidence from video surveillance cameras, which showed the alleged killer and Ashley together on Friday, the day before her body was found. After a two-day manhunt, police arrested the man late Wednesday night.

The man told police that he had no the intention of killing the woman. The two, he said, had sex and afterwards they fought. He claims to have pushed her after which she hit her head.

Earlier reports claimed the cause of death to be strangulation from a cord or a computer cable around the neck, and indicated that the incident was the outcome of an erotic encounter. Later testimony added the blow to the head as a contributing factor to the woman’s death.

“The autopsy revealed two fractures to the cranium,” said Florence prosecutor Giuseppe Creazzo, who is in charge of the case.

A forensic team spent ten hours combing every inch of the woman’s apartment, employing luminol throughout the apartment to be able to locate trace amounts of blood invisible to the naked eye. They took photos, shot video and took extensive fingerprints with cyanoacrylate.

Among the items that were seized were computer cables, clothes, sheets and paper material, along with “biological samples, a condom and a cigarette butt in the bathroom,” the prosecutor said.

A reconstruction of the crime suggests that the woman met her killer the night between Thursday and Friday, and after leaving the Montecarla nightclub, the two would have walked to her apartment, located several hundred yards from the club.

Investigators are still trying to piece together what happened in the house, but authorities believe that Olsen’s encounter with her killer was likely drug related, and could have evolved into an erotic game involving “kinky sex.”

The prosecutor said it was still unclear whether the two were lucid at the time of Olsen’s death. “We have reason to believe that they had assumed stupefying substances, alcohol for sure, and perhaps others,” he said.

Reports suggest, in fact, that the woman did not even attempt to place her hands under the cord to loosen it from her neck. In similar cases of strangulation, fingernail marks from the victim are normally present, in a desperate attempt to loosen the grip to breathe. According to one expert, such a maneuver is instinctive, “a conditioned reflex, inevitable in cases like this.” Yet on Olsen’s neck only bruises caused by the cable were found, suggesting that she may have accepted the noose willingly and had no time to react when her breath began to fail.

In days past, the alibi of the woman’s boyfriend, Federico Fiorentini, a 42-year-old Florentine painter, proved airtight.

A letter published this Tuesday by Olsen’s best friend “Jade,” in The Florentine, an English language magazine for the expat community of Florence, called Olsen “a rare and kindhearted spirit.”

We “pray that justice will be swiftly served to whoever is responsible,” she wrote.

Follow Thomas D. Williams on Twitter @tdwilliamsrome