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Immigrant families will be deported if they do not integrate into German society and their children do not fit into school, says the prime minister of Bavaria.
Edmund Stoiber, the state's Christian Democrat leader, plans to introduce the drastic measure in his regional school reforms this autumn.
The minister said: "Whoever cannot speak German will not be accepted into a regular German school. Whoever causes trouble in school will be thrown out of the class. And whoever does not integrate on a permanent basis must leave Germany."
His proposals have intensified a nationwide debate sparked by the crisis in one Berlin school whose teachers pleaded for it to be closed down because of uncontrollable pupil violence, fuelled by inter-racial tension.
Teachers at Ruetli secondary school say they have had desks thrown at them, fires started during lessons, personal possessions stolen from under their noses and are threatened daily.
The headteacher can no longer work because of stress, and the position of her deputy has been vacant for 10 years. As a result, the teachers' council has asked that the school be closed down.
The school's disintegration has been blamed on the large number of minority children enrolled there - an indication, says the liberal Free Democratic Party, that the former Social Democratic-Green-led government's "romance with a multicultural society has proved to be a complete flop".
Some 83 per cent of the pupils at Ruetli school come from non-native German families, with Arabs making up the largest group.
One former teacher, who did not wish to be named, said: "The Arabs have the say around the school and suppress the Turks."
She claimed the school was a "breeding ground for criminals and terrorists".
Many politicians blame the unruly behaviour of the migrant children on their parents, while others say it is a symptom of a failing education system.
Joerg Schoenbohm, Brandenburg's interior minister, has also suggested arresting violent or criminal pupils. "Offenders who repeatedly cause trouble in school need to know where the legal boundaries are.
"We should suspend them for a few days and put them in a detention centre or youth prison," he said, adding that the high percentage of foreign children was one of the main problems.
"The number of pupils who do not speak German should not be over 80 per cent. Foreign students should not account for more than 50 per cent of the student body."
Federal education minister Annette Schavan suggested creating boarding schools for persistent trouble-makers that combine "academic schooling, social upbringing and professional training".
Others have also called for benefits to be cut to families who do not integrate.
But MP Gesine Loetzsch of the left-leaning Die Linke.PDS party said threatening to lock up or expel immigrants was "stupid and dangerous".
"It is not only schools with large numbers of minority pupils that have problems with violence, and it is not only a migration problem but a problem with the school system," she said.
Ruetli head Brigitte Pick, who gave up her job after falling ill, said:
"The problems do not lie in the fact that a pupil is Arabic, Turkish or Serbian, but in the social background of the pupils and their lack of prospects. Last year, not one student received a training place after school."
She said teachers were not being trained properly. "These days they need to take on the role of social worker as well as teacher," she said.