PERUGIA, Italy — As bulky news vans crowd the narrow streets in this centuries-old town of 150,000, locals from the street sweeper to the traffic cop and the teacher are focusing their attention on the high-profile slaying of a 21-year-old university student from Great Britain.

They worry about how the shocking crime will affect their peaceful, sophisticated town — and Italy as a whole.

"Everybody talks about the latest developments every chance they get, but I don't think it has settled in yet to people around here," says Daniele Buonumori, a 29-year-old Perugia native who manages an orthopedic-supply store.

"This horrible thing happened in our city, in our splendid city."

More than a week has passed since British student Meredith Kercher was found with her throat cut amid evidence of a sexual attack, followed by the arrest of three suspects — including Seattle native and University of Washington student Amanda Knox, Kercher's roommate. During that time the case has lost none of its hold over this city.

"We love having the students here, we love what they bring to the city. But something like this is unimaginable," says Massimo Duranti, a local art critic, longtime City Council member and well-known public figure in Perugia.

Perugia was a popular tourist site long before the murder, but below the surface it was a less-than-idyllic city, as tensions have grown between locals and increasing numbers of immigrants from the developing world during the past decade.

Locals and Italian media commentators mention an influx of drugs. Some talk about how foreigners have driven all but a handful of locals from the city's historical center.

In July, the two-university community was the site of a raid on an al-Qaida cell operating out of a mosque on the city's periphery.

But Kercher's murder and the much-publicized arrests of three suspects so far — Knox, 20; her Italian boyfriend, Raffaele Sollecito, 23; and Congolese bar owner Lumumba "Patrick" Diya, 38 — have shaken the town in a way locals struggle to explain.

Perugia has long been a detour on the well-worn Venice-to-Florence-to-Rome tourist trail, a welcome and tranquil respite between the bustling crowds of the final two stops.

The 2,500-year-old city — known to art historians as the hometown of Perugino, the Renaissance master painter best known today as the mentor to the iconic Rafael — is the home of the renowned Perugina chocolate company and the popular Umbria Jazz Festival, held each July.

The city houses two major universities — the well-regarded University for Foreigners (which Knox, Sollecito and Kercher attended) and the venerable 700-year-old Universita degli Studi (which counts 11 popes among its alumni).

The universities account for about a tenth of Perugia's population and a large part of its identity.

Locals wonder when — if ever — things will return to the way they were before the events of the past 10 days.

"I don't know how a city recovers from something like this," Buonumori said.

It's not just Perugia: Most of Italy is following the events as they unfold. That two of three suspects are foreigners has added fuel to anti-immigration fires in some political quarters in the capital of Rome, 100 miles south of Perugia.

Italian residents from poor Eastern Europe countries and from North Africa have been implicated in lower-profile crimes in recent weeks, prompting many Italian lawmakers to call for tighter restrictions on immigrants. The Perugia murder may give those voices more clout.

On Saturday, police said a fourth suspect is being sought after evidence at the scene pointed to the possibility of another accomplice.

The Italian media reported another development as the weekend started: The stab wound to the victim missed a main artery on her neck, meaning she likely bled to death over at least two hours.

Knox's parents are in Perugia and being assisted by the Sister City Association that links Seattle and Perugia. They have declined interview requests.

The Associated Press reported that her mother, Edda Mellas, had visited Knox in jail Saturday.

"Events that have unfolded in Perugia over the last several days regarding our daughter, Amanda, have shocked and devastated our family," the family said in a statement released to the Italian media.

"We love our daughter very much and certainly stand by her through this process. We know she is probably frightened and upset about what has happened, and that she needs all the support her family can give her."

Some Italian newspapers have focused on details from Knox's profiles on social-network sites like MySpace and Facebook and graphic short stories reportedly written as class assignments to show she had a darker side.

But that's something locals, for the most part, decline to dwell on, preferring to focus on the more local aspects of the crime.

"Patrick, the bar owner, is someone we all knew and who was held in high esteem," says Duranti, who was once interviewed on the state radio network RAI along with Diya, discussing current events in Perugia.

"These young people seem like the same kind of young people who have come and gone from Perugia for years. That is part of what is so disturbing: They all seem so typical."

Eric J. Lyman is a freelance reporter based in Rome.