Abuse and torture rife at Palestinian jails: HRW
According to the report, methods employed by the Palestinian Authority included beatings and electric shocks.
On one occasion PA security forces tied a cord around a detainee's penis for eight hours, causing it to swell and turn blue, HRW said.
In Gaza, Hamas also beat and systematically abused prisoners.
Read more: The struggle for Palestinian rights: Then and now
The new report is likely to put pressure on governments that fund the PA's forces, including the US, which has maintained about $50 million a year in security funding despite cutting around $500 million in aid to the Palestinians.
"It is noteworthy that at a time when the United States has cut funding for UNRWA, which provides vital health and education services to Palestinians and to hospitals in east Jerusalem, the only source of funding remaining is to security coordination (and) to security forces that are involved in really serious abuses," Shakir said.
HRW said the report was the result of two years of research and nearly 150 interviews.
The rights group documented more than two dozen cases of dissidents arrested for no other reason than posting a critical Facebook comment or belonging to an opposition political movement.
Few security personnel have been prosecuted, the report added, and none have been convicted for abuse or torture.
Israel soldiers have long been accused of using excessive violence against the thousands of Palestinians arrested each year in the occupied West Bank and along the Gaza Strip.
Around 95 percent of Palestinians detained by Israeli forces say they were subjected to physical and mental abuse, according to testimonies from prisoners.
In February, Yassin al-Saradeeh was killed after being beaten by Israeli soldiers during his arrest in the occupied West Bank city of Jericho.
More than 40 percent of the Palestinian male population have been detained at some point by Israeli military forces since the year 2000, rights groups say.
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