The lawyer for an Australian woman arrested in the West Bank says her detention is part of a campaign by the Israeli government to silence pro-Palestinian foreigners.

Israeli soldiers arrested Bridgette Chappell, 22, in a pre-dawn raid and was held in an immigration jail in Israel. A court has since agreed to release her on bail provided she does not return to the West Bank.

The Israeli government says Ms Chappell, who was studying Arabic and politics at Birzeit University in the West Bank, was arrested for overstaying her visa.

But she was also active in the International Solidarity Movement (ISM) - a pro-Palestinian organisation committed to resisting Israel's occupation of the West Bank.

Ms Chappell was sharing an ISM apartment with two other activists - a Spanish woman and an American man, Ryan Olander.

Mr Olander says about 12 soldiers broke down the door during the night and burst in with M16 rifles.

"At about three o'clock this morning we were woken by sounds of someone fumbling with the door," he said.

"It sounded pretty violent and about five minutes after that they had used a crowbar to break the lock.

"There was about 12 Israeli military soldiers armed with M16s, flashlights and a camera."

Ms Chappell's Israeli lawyer, Omer Shatz, says he has been denied access to speak to her and fears she may be deported before he can bring her case to court.

"Usually what they try to do is try to deport her within 24 hours, using techniques of intimidation and threatening - saying 'if you won't sign a paper that's saying she is willing to leave now, or within a few hours, you will be staying there for months'," he said.

"And they know that they don't want to be in jail for a long period of time."

'Illegal' riots

Israeli authorities say Ms Chappell and her Spanish housemate were known to be involved in illegal riots and to have interfered with Israeli military activity.

But Palestinian authorities say Israel has no jurisdiction over the West Bank city of Ramallah and therefore had no right to raid the apartment.

At the time of her arrest Ms Chappell was not in Israel and Mr Shatz says if she overstayed her visa it is only because Israeli forces captured her and took her to Israel to accuse her of breaching her visa.

"The minister of interior has no authority outside Israel, and if she was brought into Israel - for example by the army - she didn't commit any offence because they put her inside Israel," he said.

The ISM says the women's arrests are aimed at stifling protests against Israel's occupation of the West Bank and that it is common for Palestinian activists to face arrest or detention for their roles in anti-Israel activities.

But Mr Shatz says in recent months Israeli authorities have begun using new tactics against foreigners who become involved.

"Foreigners like Bridgette, they take part sometimes in non-violent demonstrations, and the worst crime is that they also report to their homeland - Australia, Europe, United States," he said.

Israel has confirmed the two women are in an immigration jail but refuses to say more.