Israel's internal security service subjected Palestinians to abuse and torture while in custody, according to a report by two Israeli rights groups.
A report by B'Tselem and Hamoked said Israeli agents bound detainees to chairs during lengthy interrogations and insulted, threatened or hit them.
The report is based on interviews with 121 Palestinians held in the Petah Tikva detention centre in 2009.
Israel's Justice Ministry has denied the claims, saying it respects the law.
In a written response to the report's authors, the ministry denied many of the charges, saying interrogations were "conducted according to law in order to prevent illegal activity that would harm state security".
The report published on the B'Tselem website also includes detainees' claims that they were held in isolation, kept in "appalling" unhygienic conditions, and subjected to physical abuse and sleep deprivation.
Many reported that the interrogators used family members as a means of pressure.
The report cited the case of a 63-year-old widow who was brought to the facility apparently so that her incarcerated relatives could witness her anguish in detention. She was released without charge two days later.
The rights groups said the procedures constituted "cruel, inhuman and degrading treatment, at times amounting to torture".
The report also noted that Palestinians have filed 645 complaints with the Justice Ministry about interrogation techniques since 2001, but none has led to criminal investigations.
A statement from the ministry said that military police had opened 427 investigations of alleged violence against Palestinian detainees between 2000 and 2007.
It gave no information on any results of these investigations.