By Maayan Lubell

JERUSALEM (Reuters) - Palestinian children detained by the Israeli military are subject to widespread, systematic ill-treatment that violates international law, a UNICEF report said on Wednesday.

The United Nations Children Fund (UNICEF) estimated that 700 Palestinian children aged 12 to 17, most of them boys, are arrested, interrogated and detained by the Israeli military, police and security agents every year in the occupied West Bank.

According to the report, most of the youths are arrested for throwing stones. Israel says it takes such incidents seriously, noting that rock-throwing has caused Israeli deaths.

UNICEF said it had identified some examples of practices that "amount to cruel, inhuman or degrading treatment or punishment according to the Convention on the Rights of the Child and the Convention against Torture".

Israeli Foreign Ministry spokesman Yigal Palmor said officials from the ministry and the Israeli military had cooperated with UNICEF in its work on the report, with the goal of improving the treatment of Palestinian minors in custody.

"Israel will study the conclusions and will work to implement them through ongoing cooperation with UNICEF, whose work we value and respect," he said.

According to the report, ill-treatment of Palestinian minors typically begins with the arrest itself, often carried out in the middle of the night by heavily armed soldiers, and continues all the way through prosecution and sentencing.

"The pattern of ill-treatment includes ... the practice of blindfolding children and tying their hands with plastic ties, physical and verbal abuse during transfer to an interrogation site, including the use of painful restraints," the report said.

It said minors suffered physical violence and threats during their interrogation, were coerced into confession and not given immediate access to a lawyer or family during questioning.

"Treatment inconsistent with child rights continues during court appearances, including shackling of children, denial of bail and imposition of custodial sentences and transfer of children outside occupied Palestinian territory to serve their sentences inside Israel," the report said.

Such practice "appears to be widespread, systematic and institutionalized", it added.

"POSITIVE CHANGES"

UNICEF based its findings on more than 400 cases documented since 2009 as well as legal papers, reports by governmental and non-governmental groups and interviews with Palestinian minors and with Israeli and Palestinian officials and lawyers.

Qadoura Fares, chairman of the Palestinian Prisoners Club which looks after inmates and their families, praised the report and called for Israel to be held accountable.

A spokeswoman for Israel's Prison Service said there were currently 307 Palestinian minors in Israeli custody, 108 of whom are serving a prison sentence. Most of them, 253, are between the ages of 16 to 18 and the rest are under 16.

A senior Israeli officer in the Military Advocate General's office said one of the jailed Palestinians, aged 17 at the time of his arrest, had stabbed to death two Jewish settlers and three of their children, including a three-month-old baby, in 2011.

He denied that minors, while in interrogation, were not allowed access to family members or a lawyer. "Very few of the parents take the time to come (to the police station)," he said.

UNICEF said Israel had made some "positive changes" in recent years in its treatment of Palestinian minors, including new hand-tying procedures meant to prevent pain and injury.

It also noted a 2010 military order that requires Israeli police to notify parents about the arrest of their children and to inform minors they have the right to consult a lawyer.

The Israeli officer said the army was considering videotaping interrogations and that a new military order, coming into effect in April, will limit to 48 hours the time a minor can be held prior to appearing before a judge.

(Additional reporting by Ali Sawafta in Ramallah; Editing by Jeffrey Heller and Andrew Roche)