PERUGIA, Italy (Reuters) - An American university student on trial for the murder of a fellow British student testified on Friday that police had beaten her and suggested to her what she should say under interrogation.

Amanda Knox, 21, an exchange student from the University of Washington, is on trial along with her Italian boyfriend in connection with the death in November 2007 of Meredith Kercher.

Both women were foreign students at the University of Perugia when Kercher’s semi-naked body was found in the apartment she shared with Knox.

Prosecutors say she was stabbed in the neck when Knox, her boyfriend Rafaelle Sollecito and a third person tried to involve her in an orgy.

Knox and Sollecito say they are innocent.

“The declarations (to police investigators) were taken against my will,” she told the court, speaking in English, on the first day she testified since the trial began in January.

“Everything I said was said in confusion and under pressure and was suggested by the police and the prosecutor,” she said.

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A third suspect, 21-year-old Rudy Guede, was sentenced to 30 years in prison late in 2008 for complicity in rape and murder at a separate trial in the case.

Asked if Kercher had been raped before she died, Knox answered “I don’t know.”

“Then why did you say that to police?” a lawyer asked her.

“Under pressure, I imagined many different things. Because when I was questioned by police they suggested that she had been (raped),” Knox said.

“To make you say this, did they (the police) hit you?” the lawyer asked her

“Yes,” she said.

The trial has attracted wide media attention, particularly in Britain.

The trial is expected to go on for months. If convicted, Knox could be sentenced to 30 years in prison.