Friends of a University of Washington student being held in the slaying of a housemate in Italy said they were shocked Tuesday by the lurid details emerging from the investigation half a world away.

Several said the accusations against the 20-year-old graduate of Seattle Preparatory School couldn't possibly involve the young woman they know as studious, hard-working and talented — a woman who, in her Facebook profile, said her "top priorities are my friends and family."

"She's a very good person," said close friend Madison Paxton. "This is not something she would do."

The UW student, who is studying abroad in the central Italian city of Perugia, was being held along with two men on suspicion of the slaying and sexual assault of British student Meredith Kercher, Italian authorities said Tuesday.

Kercher, who was stabbed in the neck, apparently died fighting off a sexual attack, Perugia Police Chief Arturo De Felice said in a news conference. The Seattle Times generally does not name suspects who have not been charged with a crime.

The 20-year-old from Seattle was taken into custody along with a 24-year-old Italian man and a 37-year-old Congolese man, who owns a bar where the UW student worked. The slaying and arrests have been the subject of sensational tabloid stories in the Italian media.

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. Attorney Valerio Spigarelli, who is not connected to the case but is an expert in Italian criminal law, said if the judge confirms the detentions, the prosecutor will likely ask that the suspects remain in prison while the investigation continues, The Associated Press reported.

Spigarelli said that 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.

A U.S. State Department spokesman said that unless Americans have diplomatic status, they are subject to the local laws of the country they are staying in.

The Seattle woman graduated from Seattle Prep in 2005, where she was an accomplished soccer player and kept good grades, officials at the $11,800-a-year private school said Tuesday.

She went to study in Italy at the beginning of the school year at the University for Foreigners in Perugia, according to UW spokesman Norm Arkans. According to the woman's Facebook page, she was studying Italian and German in Perugia, a sister city to Seattle located north of Rome.

According to court records, the woman's only other brush with the law occurred earlier this year when she was fined $269 after creating a residential disturbance in Seattle. Additional details on the incident were not available Tuesday.

Paxton said she last heard from the UW student in an e-mail she received on Sunday. The e-mail detailed the student's version of the events that resulted in her arrest, Paxton said.

The student wrote that she came home Thursday after spending the night elsewhere and noticed the front door to the home she shared with three roommates was open. Her three housemates appeared to be out, she said. After taking a shower, she said, she saw drops of blood on the floor and a room looked as if it had been ransacked. She began to panic when she checked Kercher's door and found it to be locked, she wrote to Paxton.

She then called the Italian man, who is now in custody, and together they called police.

When the police came, they discovered Kercher's body in her room. The UW student was questioned throughout the weekend, she wrote to friends.

On Sunday she sent a message to Brett Prim, also a student at the University of Washington, and said she "wasn't feeling great" and that her mother was flying from Seattle to be with her in Italy.

The Associated Press reported that when her mother left to her daughter, she did not know she was a suspect.

Ron Holcomb, a neighbor, said the 20-year-old got good grades and worked several jobs to put herself through school.

"I can't believe she could be mixed up in anything like that," Holcomb said. "She would never have willingly been involved in something that led to a death."

"Ignorance is a pet peeve," the UW student wrote on her Facebook profile. "I love new situations and I love to meet new people. The bigger and scarier the roller coaster the better."

Kercher was in the third year of her European-studies degree at the University of Leeds and had gone to Italy on a one-year exchange, a university spokeswoman said.

Kercher's sister, Stephanie, described her in a news conference in Perugia on Tuesday as "one of the most beautiful, intelligent, witty and caring people you could ever wish to meet."

She added that Kercher "was pursuing her dream, and we can take some comfort in knowing that she has left us at what was a very happy time in her life."

Seattle Times staff reporter Christine Clarridge, and news researchers Miyoko Wolf and Gene Balk contributed to this report, which includes information from The Associated Press.