GAZA CITY, Gaza Strip (AP) – The Palestinians’ defiant Hamas-led government sent a new militant force into the streets of Gaza on Wednesday, disregarding President Mahmoud Abbas’ order banning the creation of the security body and raising the stakes in their deepening power struggle.

Hamas appeared to have been propelled into action by mysterious drive-by shootings that killed two of its militants in the Gaza Strip hours earlier. These and other recent cases of deadly infighting have threatened to plunge the Palestinian territories into bloody chaos.

Meanwhile, Israel reopened the main cargo crossing between Gaza and Israel, Gaza’s economic lifeline, and two Palestinians militants were killed in an Israeli raid in the West Bank.

The Hamas-led government and Abbas have been locked in a power struggle since the Islamic militant group ousted Abbas’ long-ruling Fatah party in January parliamentary elections.

Abbas, who directly controls three security forces, appointed an ally as head of the remaining three security branches, which fall under the command of the Hamas-led Interior Ministry.

In response, Interior Minister Said Siyam announced a plan last month to create the new force, which would be solely under his control.

Abbas vetoed the force, which is to number about 3,000 fighters and be headed by Jamal Abu Samhadana, a key player in ongoing rocket attacks on Israel and a suspect in the deadly 2003 bombing of an American convoy in the Gaza Strip.

Ignoring Abbas, Siyam said the unit would begin operating immediately.

Within hours, dozens of members of the armed force, all wearing the beards favored by observant Muslims, were deployed in central and southern Gaza. At the Bureij refugee camp, about 75 fighters patrolled the camp or took up positions outside.

Members of a security branch answerable to Abbas stood just a few yards away.

Siyam activated the new force just hours after masked gunmen killed a member of Hamas’ military wing before dawn in a drive-by shooting at the Jebaliya refugee camp.

On Tuesday evening, another Hamas activist was killed in a similar attack in Gaza City. Two more Hamas activists were wounded in a third shooting. Those attacks came less than a day after the cars of senior Fatah militants were blown up in Gaza City.

No one has claimed responsibility for the attacks. Dozens of Hamas gunmen, armed with anti-tank launchers, shoulder-fired missiles, hand grenades and assault rifles, turned out in a show of force Wednesday at the funeral of the militant shot Tuesday. A mosque loudspeaker announced that the family would not receive mourners “until the killers are punished.”

During the funeral procession, a voice over a loudspeaker blamed a Fatah-dominated branch of the Palestinian security forces. Mourners called on Abbas to dismiss Rashid Abu Shbak, the loyalist Abbas had appointed as a senior security commander.

Hamas’ ouster of Fatah has sparked Western aid cutoffs designed to pressure the militants to recognize Israel and disarm. The sanctions left the Hamas-led government unable to pay government salaries for more than two months.

Dozens of government employees lined up at a bank in Gaza City on Wednesday after it announced it would loan government employees up to $200 to help tide them over.

The economic distress has been aggravated by Israel’s refusal to transfer tax revenues it collects on behalf of the Palestinian Authority, and its frequent closures of the Karni cargo crossing with Gaza.

Israel reopened Karni on Wednesday, Israeli military officials and Palestinian border officials said. The military officials said this signaled a change in policy since Amir Peretz, leader of the dovish Labor Party, became defense minister earlier this month. The officials spoke on condition of anonymity because they are not authorized to discuss policy with the press.

Israel has kept Karni closed for nearly two months this year, saying Palestinian militants were trying to attack the site, as they have in the past.

The closures have created food shortages and cost the Palestinians tens of millions of dollars in lost export revenues.

While Palestinians clashed with each other in Gaza, two Islamic Jihad militants were killed and another was wounded in a pre-dawn gunbattle with Israeli soldiers in the West Bank town of Nablus, Palestinian security and medical officials said.

Troops on an arrest raid circled the militants’ five-room, one-story hideout and a firefight broke out. Fighting continued for hours, and troops used a bulldozer to raze part of the building,

A large pool of blood stained the ground outside the house. “God is Great” was daubed in blood on the wall around the building.

Palestinian negotiator Saeb Erekat condemned the killings “in the strongest possible terms.”

A spokesman for Islamic Jihad who gave his name only as Abul Abed said the group would not give up its fight against Israel.

“This gives us more courage to fight them,” he said after viewing the two bodies. “We are fighting with Israel for billions of Muslims in the world.”

The Iranian-backed Islamic Jihad has responsible for all nine suicide bombings against Israeli targets since Palestinian militant factions agreed to an informal truce in February 2005.