Israel plans to use detention without trial against Jewish extremists suspected of anti-Arab hate crimes, a minister has announced, amid mounting criticism over government failure to secure prosecutions.

Internal Security Minister Yitzhak Aharonovitch told Army Radio on Wednesday that the government intended to use "administrative detention against those carrying out so-called 'price tag' attacks".

"Price tag" is a euphemism for hate attacks by Jewish extremists predominantly targeting Palestinian and Arab-Israeli property.

As police confirmed yet another incident of nationalist-inspired vandalism, in which "Death to Arabs" and other racist graffiti was found in northern Israel, senior law enforcement officials were to discuss with ministers how to halt the attacks.

Administrative detention allows for suspects to be held without trial for up to six months.

Such orders, which can be renewed indefinitely by a court decision, are almost exclusively used against Palestinians suspected of security-related offences.

Although police have made scores of arrests, there have been no successful prosecutions for price tag attacks and the government has come under mounting pressure to authorise the Shin Bet internal security agency to step in.

"It is a matter of days or even weeks until these people are caught and investigated, and I hope they will be brought to justice for their actions," said Aharonovitch who was to meet with Justice Minister Tzipi Livni and top police and security officials later on Wednesday.

'Incitement of violence'

Livni said on Sunday she would back the idea of defining such acts as "terrorism" after the US State Department for the first time included mention of price tag attacks in its global report on terror.

Police on Wednesday confirmed the arrest of a young woman from Yitzhar, a bastion of hardline Jewish settlers in the northern West Bank, after she posted remarks online allegedly justifying the use of violence against Israeli soldiers.

"She was arrested overnight and her personal computer was confiscated," police spokesman Micky Rosenfeld told AFP news agency, saying she was suspected of "inciting violence against soldiers."

"I am in favour of throwing stones in certain situations, even if the stone leads to a soldier's death," she wrote, according to a transcript of the alleged online correspondence obtained by Yediot Aharonot newspaper.

The suspect told the paper her comments were taken "out of context."

Police on Monday extended the detention of another Yitzhar settler on suspicion of involvement in an April 18 arson attack on a mosque in the overwhelmingly Arab town of Umm al-Fahm in northern Israel.