PASSAU, Germany — The stabbing of the police chief here in December provoked a nationwide furor because the victim, Alois Mannichl, was known as a staunch opponent of neo-Nazis, who were immediately blamed for the attack.

But the loud public protests and demonstrations in the streets of Passau gave way to silence, as days stretched into weeks and the case remained unsolved. Speculation that the perpetrator was a member of the police chief’s family ran rampant, from local gossip all the way up to the leading newspapers and magazines in Germany.

What had become an instant symbol of out-of-control right-wing violence quickly turned into an investigation under the microscope. Here in this ancient city, which traces its history back to Roman times and earlier, the case and its aftermath have dredged up a reputation for ties to Nazism that civic leaders had worked hard to shed.

Now two months after the crime shook the country, the police and prosecutors here said Wednesday in a statement that they were more or less back to square one, ruling out Mr. Mannichl’s wife and children while still searching for a man who is 6-foot-3, powerfully built, with close-cropped hair and possibly a tattoo on his neck, the same description released Dec. 14, the day after the attack.

“At this point, there is no evidence that the crime was committed by anyone in the family circle,” said the statement. The 50-member special investigative commission established in the days after the attack is investigating “in all directions,” but has no “hot lead” at this stage, the statement said.

The attack on Mr. Mannichl, which was serious but not fatal, renewed calls nationwide for a ban against the far-right National Democratic Party, known by its German initials as the N.P.D. It also further inflamed concerns about a rise in violence by the extreme right.

In the state of Bavaria, where Passau is located, the number of right-wing-motivated assaults rose to 76 in 2007 from 42 in 2006, the most recent government figures available. But the newspaper Frankfurter Rundschau has reported unreleased figures that through the first 10 months of 2008, right-wing violent crimes increased 15 percent nationwide.

Mr. Mannichl has been known for his hard line against the extreme right, but earned the particular enmity of neo-Nazi groups after ordering the opening of the grave of a prominent former Nazi, Friedhelm Busse, after his death last July. Mr. Busse was buried with a flag bearing a swastika, which is outlawed in Germany, and the police removed the flag as evidence.

Around 5:30 p.m. on Dec. 13, an attacker plunged a knife into Mr. Mannichl’s chest outside his home on a quiet residential street in the tiny town of Fürstenzell near Passau, narrowly missing his heart, according to news reports. Mr. Mannichl said after the attack that his attacker yelled, “Greetings from the national resistance” and “You won’t be trampling on the graves of our comrades anymore.”

The attack made headlines nationwide, as did a candlelight vigil in Mr. Mannichl’s honor. “When anyone is attacked by a right-wing extremist, it is an attack on us all,” said Chancellor Angela Merkel in an interview the next week.

The day after the attack, the police arrested two men, ages 26 and 27, in connection with the crime. Two days later, a couple from Munich were detained for questioning as potential accomplices.

Yet all four were quickly released. And the questions began to mount, in particular around the fact that the knife used in the attack reportedly came from Mr. Mannichl’s house. He explained that it had been used for cutting gingerbread during a neighborhood Advent celebration and that it had been left outside, where the assailant could have picked it up.

Heinz Fromm, the president of the domestic intelligence agency, the Federal Office for the Protection of the Constitution, said publicly that the office had no evidence linking the crime to right-wing extremists. And conjecture about the case, and Mr. Mannichl, evolved into a popular parlor game from Passau clear to the capital, Berlin.

The national news magazine Stern later reported that it was “more or less being openly speculated that the police chief could have been the victim of a family drama” and might have sent his own police force on a wild goose chase.

Other possibilities aired publicly included the attacker was from the punk or goth scene or was an angry criminal out for revenge who only pretended to be a neo-Nazi to disguise his identity.

Mr. Mannichl declined to be interviewed for this article, but told a Munich newspaper last month that he was trying to live with the “virulent speculation.” He described the questions surrounding the case as “a deep valley” in his life.

Members of the local N.P.D., who have long accused Mr. Mannichl of harassment, organized a protest against what they called unfair “baiting” of the right wing in connection with the case. On Jan. 4, some 200 far-right demonstrators from all over Germany gathered in Passau, where they were confronted by roughly 1,000 counterprotesters and nearly as many police officers. There were several arrests but no violence.

For Passau, a city of 50,000 that sits at the confluence of three rivers, the Inn, the Ilz and the Danube, and seeks to lure tourists to the narrow lanes of its quaintly lovely medieval old town, it was all an unwelcome return to what officials call an unfair reputation as a “brown city,” a reference to the brown shirts that came to identify the Nazi party.

Passau gained international notoriety as a symbol of Germany’s uneasy relationship with its past in the Academy Award-nominated film “The Nasty Girl,” based on the true story of Anna Rosmus, who faced death threats when she began looking into the Nazi past of her hometown in 1980 when she was 19.

Passau remained a popular gathering spot for the far right, both the N.P.D. and the German People’s Union, until just a few years ago, because of its connection to famous Nazis (Hitler lived here for two years as a child) but also because they could hold their local gatherings in Nibelung Hall, a 1934 example of Nazi architecture.

But the city has steadily evolved into a more cosmopolitan, open place. A university established here in 1978 brought 8,000 students and a cultural shot in the arm.

The fall of the Iron Curtain and the integration of Europe has turned Passau’s location in what was once an isolated corner of Germany into a crossroads and a destination. Nibelung Hall was torn down in 2004, and its replacement is called the Dreiländerhalle, or Hall of Three Lands.

http://www.nytimes.com/2009/02/12/world/europe/12passau.html?ref=todayspaper&pagewanted=print

Copyright 2009 The New York Times Company