A drug dealer suspected of involvement in the murder of Meredith Kercher had sex with her on the night she died, DNA tests have revealed.

Italian police last night said that DNA taken from the toothbrush of Rudy Hermann Guede, 20, matched samples found on Ms Kercher’s body and on toilet paper in the house where she was murdered.

Mr Guede, who has dual Italian and Ivorian nationality, was arrested in Germany on Tuesday nearly three weeks after he left Perugia following the murder of the British student.

The scientific evidence emerged after it was revealed that Amanda Knox, the American student who is also a suspect, told police after she was arrested that she was “very confused” about who had cut her housemate’s throat but insisted that she was not the killer.

New witness 'saw Meredith suspects together'

Amanda Knox, Raffaele Sollecito and Rudy Guede were see at the house in Perugia where the American student died

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• Murder in Perugia

BACKGROUND

• Meredith Kercher: Q&A

• New DNA not from Meredith suspects

• Timings crucial to Kercher murder investigation

Related Links

• 'I didn’t cut Meredith’s throat'

• Meredith suspect claims innocence

• Meredith suspect arrested in Germany

In a rambling three-page statement, leaked to the Italian press yesterday, Ms Knox appears to have tried to redirect police suspicion to her Italian boyfriend, Raffaele Sollecito. The day before, she had accused Diya “Patrick” Lumumba, a Congolese bar owner.

“Who was the real murderer?” she wrote. “Why did Raffaele lie? What made me think of Patrick?”

Mr Lumumba, who spent two weeks in prison, was released this week for lack of evidence. Police suspect that Ms Knox named Mr Lumumba as the killer to cover up for Mr Guede, whom they began looking for after a fingerprint found in the house was not that of any of the three suspects in custody at the time.

Last night’s results showed Mr Guede’s DNA matched that found on a tampon which indicated that Ms Kercher had what was described as “violent” sex on the night she died.

It also matched the DNA found on toilet paper in the bathroom.

Mr Guede had earlier admitted being in the house on the night of the murder but said an Italian man he did not know had committed the crime.

During a private conversation with a judge in Germany, leaked to Italian newspapers, he claimed he was in the bathroom when he heard Ms Kercher scream and tried to resuscitate her when he found her throat had been slit.

One of Mr Guede’s lawyers, Vittorio Lombardo, said the test results did not mean his client was guilty. He said: “These results need to be carefully looked at. Rudy has not denied being in Meredith’s house, and the tests do not say that the sex was not consensual.

“Rudy maintains he was in the bathroom when Meredith was killed, and these tests do not show anything which contradicts that.”

Ms Kercher, 21, from Coulsdon, South London, was found dead on November 2 in her bedroom at the house she and Ms Knox shared with two Italian women. No trace of Mr Lumumba’s DNA was found there.

Il Messaggero reported yesterday that an unnamed woman professor had told police that she heard a “terrifying scream” as she passed the cottage at 2am. This would appear to be at odds with the official time of death, which pathologists originally put at between midnight and 2am but then moved back to between 10pm and midnight.

The paper said that a female student who lives near the murder scene had testified that she heard “strange noises” from the cottage garden at 1am, while another had said that a “coloured man” rushed past her from the direction of the cottage at 10.30pm.

Ms Knox admitted that she and Mr Sollecito had smoked marijuana on the day of the murder. Her memory was confused partly because of the drug but also because she was “in a state of shock and exhausted”. She wrote: “I have serious doubts about the truth of my declarations. This is all very strange, I know, but what happened is as confusing for me as anyone else.”

On the evening of the murder she had been at Mr Sollecito’s flat, she said.

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