Clashes in the Gaza Strip have left six Palestinians wounded, a day after a major security operation began aimed at try to curb violence and lawlessness.
Police from both main rival factions have deployed in Gaza
Hundreds of troops, some loyal to rival factions Hamas and Fatah, fanned out on the streets of Gaza on Thursday.
Up to 400 people have died in clashes between Palestinian factions since the Islamist Hamas won last year's parliamentary elections.
But the rival parties agreed to form a coalition government earlier this year.
On Friday, a number of Palestinians, including civilians and security officers from forces controlled by Palestinian Authority President Mahmoud Abbas, were wounded in shootouts in Gaza City.
A further two civilians were hurt when militants from the armed wing of Hamas opened fire in the Jabaliya refugee camp north of Gaza City, the AFP news agency reported.
The circumstances surrounding this incident are not clear.
Wave of violence
Since the Israeli withdrawal from Gaza in 2005, the strip has seen a wave of infighting, armed robberies, deadly family feuds and kidnappings.
Several attempts to halt the violence have failed, and the interior minister in the new Palestinian coalition government, Hani Qawasmi, has threatened to resign because he says his plan for restoring security has not been carried out.
As many as 3,000 police were reported to have taken part in the initial operations launched on Thursday, the Associated Press reported.
One official told the AFP news agency that troops took up positions in the north of Gaza at entrances to towns and at major road junctions.
Witnesses said that security personnel were inspecting vehicles on the approach to Gaza City and asking passengers to show their identity cards.
Officials said that forces loyal to Fatah and Hamas would now wear the same police uniform and answer to the interior ministry, which has been placed under the control of Mr Qawasmi, a political independent in the coalition government.
The full details of the security plan are not known.
The first phase was set to last 100 days and to cover traffic and crime fighting, the Associated Press said.