Edda Mellas, of Seattle, arrived in Perugia on Tuesday night and was being hosted in a city-owned apartment, city spokesman Paolo Occhiuto said.
Mellas' daughter, Amanda Marie Knox, a 20-year-old University of Washington student, was detained Tuesday along with her 24-year-old Italian boyfriend Raffaele Sollecito and a Congolese resident of Perugia, Lumumba "Patrick" Diya, 38, in connection with the sexual assault and death of British student Meredith Kercher.
Perugia police did not release the suspects' names, but a police spokeswoman confirmed Wednesday that the names that had appeared in the Italian media were correct.
Kercher, 21, was found dead Friday, half-naked, in the apartment she shared with Knox after attending a Halloween party, authorities said.
Police chief Arturo De Felice said Tuesday she died fighting off a sexual attack. The coroner said Kercher was stabbed in the neck, but police say no murder weapon has been found.
In Italy, police detain people as suspects if prosecutors feel they have sufficient proof that they were involved in a crime. Within 48 hours, a judge must decide at a hearing whether to confirm the detentions or reject them based on the prosecutors' evidence.
That hearing is scheduled for Thursday. If the judge confirms the detentions, the prosecutor will likely ask that the suspects remain in prison while the investigation continues, said attorney Valerio Spigarelli, who is not connected to the case but is an expert in Italian criminal law.
At a later date, depending on the course of the investigation, prosecutors may ask a judge to formally indict the suspects and put them on trial, Spigarelli said.
Members of Kercher's family, meanwhile, arrived Tuesday in Perugia and were being hosted at the city's expense at a central hotel, awaiting word from prosecutors on when they can take her remains home, Occhiuto said in a phone interview.
"We don't know how long it will take," he said.
In Seattle, the president of the Seattle-Perugia Sister City Association, Mike James, said it helped make travel arrangements for Mellas to get to Perugia. At the time she left, she was going to comfort her daughter and did not know she was a suspect.
Occhiuto said Mellas had been informed during the trip that her daughter had not just been questioned by police in the case but had been detained.
A spokesman for the University of Washington in Seattle, Norm Arkans, said Knox was a student in good standing, studying this quarter in Perugia.
"That's all we can say because of student information privacy," Arkans said. "We don't have a role in any student's private legal problems."
Perugia, a city of about 150,000 people, hosts two major universities, the Italian state University of Perugia, with some 20,000 students, as well as the University for Foreigners, with a few thousand students, Occhiuto said.
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