The UN human rights investigator for Gaza and the West Bank called on Israel on Thursday to investigate what he called excessive force used by Israeli security against Palestinians and to prosecute perpetrators.

Makarim Wibisono, U.N. special rapporteur on human rights in the Palestinian territories, also told Israeli authorities to charge or release all Palestinian prisoners being held under lengthy administrative detention, including children.

“The upsurge in violence is a grim reminder of the unsustainable human rights situation in the Occupied Palestinian Territory and the volatile environment it engenders,” he said in a final report to the Human Rights Council.

Twenty-seven Israelis and a U.S. citizen have been killed since October in near-daily Palestinian attacks that have included stabbings, shootings and car-rammings. Israeli forces have killed at least 157 Palestinians, 101 of them assailants, according to Israeli authorities.

Israel’s foreign ministry dismissed the report as biased.

“The report reflects the one-sidedness of the mandate and its flagrant anti-Israel bias. It is this one-sidedness which has made the rapporteur’s mission impossible to fulfill, hence his resignation,” spokesman Emmanuel Nahshon said.

“COLLECTIVE PUNISHMENT”

Wibisono announced his resignation from the independent post last month, effective March 31, accusing Israel of reneging on its pledge to grant him access to Gaza and the West Bank.

Wibisino said on Thursday the upsurge of violence came against a backdrop of “illegal” Jewish settlements in the West Bank, including East Jerusalem, construction of a wall, and Israel’s blockade of Gaza that amounted to a “stranglehold” and “collective punishment”.

Israel must address these issues to uphold international law and ensure protection for Palestinians, he said.

Israel captured the West Bank, Gaza Strip and East Jerusalem in the 1967 Middle East war and later annexed East Jerusalem, declaring it part of its eternal, indivisible capital, a move never recognized internationally.

About 5,680 Palestinians were detained by Israel as of the end of October 2015, including hundreds of minors, Wibisono said, citing figures from the Israeli human rights group B’Tselem.

Regarding those under administrative detention, he said: “Hundreds of Palestinians being held, now including children, often under secret evidence, and for up to six-month terms that can be renewed indefinitely, is not consistent with international human rights standards.”

“The government of Israel should promptly charge or release all administrative detainees.”