Dounia and Khouloud will now have to study from home

They join two girls expelled on Tuesday - one of whom told a French newspaper it had destroyed her life.

The expulsions came as the education ministry gave schools the go-ahead to begin proceedings against 72 students who have refused to obey the law.

The law bans conspicuous religious symbols in schools and is meant to protect the principle of secularism.

But many Muslims protest it is a fundamental breach of human rights and is intended as a specific attack on their religion.

My classmates liked me just the way I was Khouloud, 12

On Wednesday, two girls named only as Manele, 17, and Tuba, 16, were excluded from schools in Mulhouse, eastern France.

Another unnamed girl was expelled from a school in Flers, Normandy.

Two French journalists, Christian Chesnot and Georges Malbrunot, remain hostage in Iraq after the French government refused to accede to kidnappers' demands to withdraw the new law, which came into force last month.

Girl's anger

On Tuesday, 12-year-old Dounia and 13-year-old Khouloud left their secondary school, also in Mulhouse, for the last time.

"They have just destroyed my life," Khouloud told Le Monde newspaper.

She said she had been a good student and hoped to become a doctor.

"My classmates liked me just the way I was. They didn't ask me to show my hair before electing me class delegate last year."

France's Sikhs have realised they too will be affected by the law

Both girls will now study by correspondence course.

The school they were attending says it tried to mediate with the girls' families, but could reach no compromise.

But Education Minister Francois Fillon says the vast majority of disputes - which he says numbered 600 at the start of the school term - have been resolved.

France always knew that implementing this law would not be easy, says the BBC's Caroline Wyatt in Paris.

Many people view the law's stated aim - of ensuring that French schools remain secular - with scepticism.

Its origins appear to be more firmly rooted in French fears of an increasingly fundamentalist form of Islam being practised by a younger generation of French Muslims, our correspondent says.

Sikh alarm

The law also applies to other religious symbols such as large Christian crosses and Jewish skullcaps.

France's Sikh community, which was never consulted on the law, has only belated realised it applies to Sikh turbans too, reports our correspondent.

Three Sikh boys excluded from lessons despite wearing only the under-turban have now taken their case to court in Bobigny, outside Paris.