The ruling Hamas movement on Wednesday replaced hundreds of striking teachers with its own supporters, purging Gaza's education system of its political rivals and deepening its control of the coastal territory.

The labor strife has disrupted the public school system at the start of the academic year and added to the misery in Gaza, which has suffered from international isolation and Israeli economic sanctions since Hamas violently seized power last year.

During the takeover, Hamas routed forces loyal to the rival Fatah movement. The local teachers' union, one of the last remaining Fatah strongholds in Gaza, called its strike this week to protest the transfers of dozens of educators to new schools. It said Hamas forced the transfers to give its supporters key posts in the education system.

Hamas denied this, but then installed hundreds of new teachers almost immediately after the strike began.

"Anybody who left their job will not be allowed to return," said the Hamas education minister, Mohammed Askoul. "They have become irrelevant and cannot be trusted anymore as educators." He estimated 2,000 teachers have been replaced. About 9,000 teachers work in Gaza's public schools.

The move ensures Gaza's education system will now be stacked with Hamas loyalists. While the group has said it would not impose its strict Islamic views on society, its control of the classrooms is likely to change the tone of instruction and create more sympathy for the group's ideology among the territory's 250,000 public school students.

The dispute has caused widespread confusion in Gaza's schools this week. Many parents kept their children home. Some students appeared torn, coming to school but skipping class. Police in cars and on horses patrolled around school areas.

"What's happening is a joke. We came to school and the teachers told us to go home," said Hussam Abdullah, 16, standing outside his school in Gaza City. "But the new (Hamas) principal says if we don't go to school for a week, we'll be expelled."

Following the Hamas takeover, the Palestinians were left with two governments: the Hamas regime in Gaza and the Fatah-dominated administration of President Mahmoud Abbas in the West Bank.

The two governments have shared the same educational curriculum and exams — one of the few last things the rivals had in common. But that could soon change.

Abbas' government, which pays teachers' salaries, is now seizing upon the strike as a loyalty test.

Bassam Zakarneh, a union leader, said Abbas' government would fire teachers who accept school promotions — because it indicates loyalty to Hamas.

The Palestinian Center for Human Rights, an independent rights group, said the threat was effectively against any teacher who did not participate in the strike. Teachers in Gaza have also understood the threat this way.

"This is a disaster," said Aly, a 47-year-old math teacher who declined to give his full name for fear of offending Hamas or Fatah. "The big losers are me and my students."

Wael, a 38-year-old physics teacher and Fatah loyalist, said he felt bullied into obeying the strike.

"My salary and future are tied to the side that pays me," he said. "At the same time, I am afraid there'll be (Hamas) procedures taken against me." He declined to give his last name because he did not support the Fatah strike and feared his salary would be cut.

Fatah loyalists darkly warned Hamas appointees would transform Palestinian schools into Taliban-style madrassas.

"They will turn the schools into centers for their black propaganda," said Zakarneh, the union leader.

Hamas police have arrested three school principals and interrogated dozens of strikers since the stop-work protest began, said Khalil Shahin of the Palestinian Center for Human Rights.

However, he said it was unlikely Hamas will dramatically alter the Palestinian curriculum. Schools already teach the Islamic faith, and the Hamas government has not made any moves to increase the number of hours of religious studies since it came to power last year.

Instead, Shahin said children would likely be exposed to more subtle attempts to make them adopt Hamas' militant creed.

"Unfortunately there's a tone, a direction to 'correct' some of the curriculum. You could say it's like they have their own quiet curriculum," Shahin said.