BERLIN, JAN. 11 -- Three neo-Nazi skinheads carved a swastika into the cheek of 17-year-old girl in a wheelchair after she refused their order to shout fascist slogans, German police said today.

The assailants allegedly attacked the girl with a knife Monday after she emerged from a public toilet for the disabled in the eastern city of Halle, about 125 miles southwest of Berlin, a police spokesman said.

After she refused the attackers' demand that she shout "Gas the cripples!" and "Foreigners out!" the three cut a crude swastika in the left side of her face, according to Police Chief Guenter Hermann.

Reports of the attack sparked outrage from groups for the disabled and politicians across Germany. As part of the wave of right-wing violence plaguing the country since reunification in 1990, scores of people who use wheelchairs or otherwise are disabled have been attacked or harassed.

Although violent crimes linked to right-wing assailants dropped by more than 25 percent in 1993 compared with the previous year, horrific accounts of neo-Nazi thugs preying on the weak or defenseless remain an almost daily occurrence in Germany. Government statistics indicate that of 2,456 acts of right-wing violence in 1992 -- a 30-fold increase in a decade -- about 90 percent of the victims were foreigners and the remaining 10 percent "leftists, homosexuals and disabled persons."

For example, two skinhead youths went on trial today in the western German town of Siegen for allegedly kicking to death a 55-year-old man who was nearly blind. The indictment accuses the defendants, who apparently did not know their victim, of "kicking the defenseless man violently with their heavy boots, alternating among the head, neck and chest."

In another episode reported today, three drunken right-wingers in the eastern city of Erfurt allegedly molested a pregnant 23-year-old Nigerian woman at a railway station. But there was no confirmation of an initial police report that the woman had been kicked in the stomach by the assailants, who denied the accusation.

For many here, hostility toward the disabled evokes chilling memories of the massive euthanasia program concocted under the Nazi regime, when thousands of physically and mentally disadvantaged people were exterminated as part of an effort to purify the "Aryan" race.

A few recently reported attacks have subsequently been exposed as frauds by purported victims seeking sympathy or insurance money. A 14-year-old girl who claimed a swastika was cut into her face in November 1992 later admitted having fabricated the story.

In the Halle incident, the victim suffered a cut measuring roughly 1-by-1 1/2 inches, which "will be visible for quite a while," police spokesman Ralf Berger told the Reuter news agency. "But the chances are good that there will be no permanent scar."

More than 100 police officers are searching for the suspects, and about 200 known right-wing radicals have been questioned, Berger said. Authorities said they are looking for two men, aged 18 to 20, and a 15-year-old female accomplice.

The victim was treated at a local hospital and released. Although initially too distraught to talk to investigators, she subsequently helped police prepare a composite sketch of the attackers, Berger said. The girl and her parents are under police protection, he added.

President Richard von Weizsaecker denounced the attack as "an unacceptable infamy." In Bonn, Justice Minister Sabine Leutheusser-Schnarrenberger declared that "violence against the weak, above all against disabled people, is especially detestable and must be publicly repudiated." The justice minister noted that a proposed federal law would raise the maximum sentence for aggravated assault in such cases from three years to five.