Ismail Haniyeh looks on as he receives congratulations from ministers and diplomats at the Council of Ministers in Gaza City

The Islamic militant group Hamas is taking steps to halt a round of internal Palestinian unrest, just days after its new government was sworn in.  Seizing control of the chaotic streets is emerging as Hamas' first major test.

Palestinian Prime Minister and Hamas leader Ismail Haniyeh has ordered gunmen off the streets of the Gaza Strip, after deadly clashes among rival militias.

The unrest erupted on Friday, after a commander of the Popular Resistance Committees, a small militant group, was assassinated. The group accused security forces loyal to Palestinian President Mahmoud Abbas of assisting Israel in the killing of Abu Yousef Abu Quka, who died when his car exploded in flames in Gaza City. Israel says it was not involved.

Gunmen clashed at Abu Quka's funeral, leaving three Palestinians dead.

Armed supporters of Fatah movement in Gaza

The unrest poses a serious challenge for the new Hamas government, which assumed power earlier this week. Mr. Haniyeh said the fighting was "dangerous and must not be repeated."

Former Palestinian Cabinet Minister Saeb Erekat of the defeated Fatah party agrees.

"This is the interest of all Palestinians, for their social fabric, for their economic fabric, for political fabric, they must maintain one gun, one authority, the rule of law, for the sake of the Palestinian interests," he said.

Hamas is now seeking solutions to a problem that it helped create. Before it was in power, Hamas, with its well-armed and independent militias, made it difficult for the previous Palestinian Authority to impose the rule of law.

Now, the tables are turned. The security forces, which are dominated by Fatah, may be reluctant to cooperate with the Hamas government. Hamas was elected on a platform of restoring law and order, but it is not clear if anyone can control a turbulent territory where dozens of often rival militias rule the streets.