At least 50 people were hurt in a clash on Sunday between Palestinian police and the residents of a West Bank refugee camp who were protesting against a pay strike in a United Nations aid agency.
Palestinian employees were demanding higher pay.
The demonstration at Jalazoun camp was the worst in a series of protests in the past week.
Forty of the injured were police officers.
The United Nations Relief and Works Agency employs more than 5000 people in 19 camps holding about 730,000 West Bank refugees
Because of the strike, the UNRWA has had to close schools and clinics, and suspend rubbish collection at the camps.
Aid agencies are struggling to cope with a deepening refugee crises related to the civil war in Syria at the same time the Palestinian economy is faltering.
The UNRWA has said it is trying to end the strike but does not have funds to meet the wage demands.
It also says its employees get paid at least 20% and in some cases 80% more than public-sector employees in equivalent fields.