Authorities in the West Bank have launched an investigation after the death of a 40-year-old man who was taken into Palestinian custody.
The family of Ayman Abu-Sufian said he was diabetic and suffered from high blood pressure before he passed away on Friday. Abu-Sufian was detained on Wednesday and charged with assault.
Human rights groups criticized the government for mistreating its detainees in Palestinian prisons.
An official, who spoke on condition of anonymity, said Saturday that the Palestinian attorney general has launched an investigation.
Last week, a Palestinian detainee died in custody in Israel. Palestinian officials alleged that detainee was tortured, while Israel denied mistreatment and said more tests are needed to determine the cause of death.
The death of the 30-year-old man sparked protests in the West Bank.
A further surge of unrest in the occupied West Bank has raised fears in Israel of a new Palestinian Intifada, or uprising.
Palestinians rioted at several locations across the West Bank on Friday and Israeli troops used tear gas and rubber bullets against the rioters, the Israeli spokeswoman said.
At least one Palestinian was seriously hurt after being hit in the head by a rubber bullet, a Palestinian ambulance worker said.
The rioters have come out in support of Palestinians held in Israeli jails and to express frustration at Israel's expansion of Jewish settlements in the West Bank.
Further clashes erupted on Friday when Israeli soldiers shot and wounded three Palestinians in the Gaza Strip as a number of violent incidents erupted along the border with Israel, Palestinian medics and an Israeli military source said.
The new bout of violence came three days after Palestinian militants launched a rocket from Gaza into southern Israel for the first time since the Nov. 21 truce brokered by Egypt ended eight days of cross-border air strikes and rocket attacks.
An Israeli military spokeswoman said Palestinians hurled rocks and firebombs over the fence at army patrols in several locations and that militant gunfire damaged an army vehicle, a first such incident since the truce took effect.