DNA ANALYSIS OF a condom and cigarette butt led Italian prosecutors to arrest a Senegalese man in the death of an American woman in Italy.

Ashely Olsen suffered two fractures to her skull before being strangled in her Florence apartment, local police said today.

The naked body of Ashley Olsen, 35, of Summer Haven, Florida, was discovered Saturday morning by her boyfriend.

Florence chief prosecutor Giuseppe Creazzo told a news conference that investigators had detained Tidiane Cheik Diaw, a 25-year-old Senegalese immigrant, based on witness testimony and DNA analysis, and also because he had Olsen’s cell phone.

He said Diaw had offered “substantially admissive” testimony in response to the accusations during a preliminary interrogation that lasted until 4am this morning. Diaw has not yet been charged.

Citing witness testimony and street cameras, Creazzo said Olsen and Diaw met for the first time at the Montecarla disco in Florence early Friday morning and went together to Olsen’s apartment in the Tuscan city’s historic centre.

He said they had consensual sex. Both had drunk alcohol and possibly taken drugs over the course of the night.

Flowers laid outside the apartment where the 35-year-old was found dead. AP AP

He said the autopsy determined that Olsen had suffered two fractures to her skull that were so violent they alone would have killed her. She was subsequently strangled.

Police detained Diaw after DNA analysis came back from a used condom and cigarette butt found in Olsen’s bathroom, as well as DNA samples taken from under her fingernails.

Diaw was also tied to the crime because he had taken Olsen’s cell phone, put his own SIM card in it and used it, Creazzo said.

“We have gathered serious indications of guilt against him,” Creazzo said, adding however that a judge must confirm the arrest.

Olsen was involved in fashion and had moved a few years ago to Florence. AP AP

Prosecutors didn’t say if Diaw had a lawyer or had been assigned a court-appointed lawyer.

Creazzo said Diaw had arrived in Italy illegally a few months ago to join his brothers who had been there for some time. He told investigators he was working odd jobs handing out flyers for local nightspots.

Diaw is accused of aggravated homicide, given the brutality of the death and that Olsen was in a compromised state, Creazzo said. He remains in detention.

Olsen moved to Florence a few years ago and was active in the expatriate arts scene. Her father is a professor at a local design institute.

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