Thirteen people were arrested on Sunday as Gaza security forces broke up a demonstration backing Palestinian president Mahmoud Abbas ahead of key talks at the White House, organizers said.
The rally was organized by Abbas's Fatah party which is the dominant faction in the West Bank-based Palestinian Authority, but a minority in the Gaza Strip which is ruled by the rival Islamist Hamas movement.
Fatah official Mohammed Nahal said police attacked around 80 demonstrators as they were gathering in the square of the Unknown Soldier in Gaza City.
"The police and Hamas's internal security forces attacked them and dispersed the demonstration. They arrested 13 people and beat up others," he told AFP.
Police spokesman Ayub Abu Shaar confirmed the arrests, saying the protesters had no permit.
"Police broke up a gathering of a group of people who were demonstrating... because it was unauthorized," he told AFP.
Abbas will meet US President Barack Obama on Monday to discuss the crisis in peace talks with Israel ahead of a looming April deadline.
Obama met Prime Minister Benjamin Netanyahu earlier this month as part of a Herculean effort to convince both sides to agree to a framework proposal to extend the talks to the year's end.
The American president urged Netanyahu to make "tough decisions" and warned him against "international repercussions" for Israel should the talks fail.