GAZA CITY, Gaza Strip – The Hamas government yesterday named a Palestinian Arab whose group has attacked Israel and was blamed for bombing an American convoy to head a new security force made up of Islamic militants.

The move is a direct challenge to the authority of Palestinian leader Mahmoud Abbas, and was quickly denounced by Israel and America.

The Hamas interior minister, Said Siyam, issued a decree appointing the head of the Popular Resistance Committees, Jamal Abu Samhadana, as director general of his ministry.

Mr. Samhadana, a former security officer who was dismissed for refusing to report for duty during the uprising against Israel, was given the rank of colonel.

His group is responsible for many of the homemade rockets launched at Israel in recent weeks. It also is suspected by some of involvement in the attack on an American Embassy convoy in Gaza that killed three Marine security guards in October 2003.

An Interior Ministry spokesman, Khaled Abu Hilal, said Mr. Siyam would form a new security branch – answerable only to him – to bring law and order to the Palestinian Arab streets.

“This force is going to include the elite of our sons from the freedom fighters and the holy warriors and the best men we have,” he said. “It’s going to include members of all the resistance branches.”

Mr. Abbas’s office had no immediate response.

In Washington, a State Department spokesman, Sean McCormack, criticized the move. He said it showed “the true nature and the true tactics of this particular Hamas-led government,” and America would still hold the Palestinian Authority responsible for stopping terror attacks.

An Israeli Foreign Ministry official, Gideon Meir, echoed that.

“If someone needed proof about the connection between the Hamas rule and Palestinian terror, this appointment is the ultimate proof,” he told the Associated Press. “It’s like allowing the fox to guard the chicken coop.”

Mr. Abu Hilal said officials have begun recruiting for the new force, but they could not say how it would be structured or how big it would be. He also did not know whether the new force would be paid by the Interior Ministry or serve as volunteers, paid by their terrorist groups.

After Hamas’s January 25 election victory over Mr. Abbas’s Fatah Party, the Islamic group’s leaders said they planned to incorporate some of their militants into the security forces. But the announcement of a new force made up of militants appeared to be an effort to counter Mr. Abbas’s moves to take control of all other security branches.

Soon after the Hamas-led Cabinet was sworn in late last month, Mr. Abbas appointed a longtime ally, Rashid Abu Shbak, to head the three security services that were supposed to fall under Hamas command. Mr. Abbas also controls several other security services.

Mr. Samhadana is high on Israel’s wanted list and has been the target of at least one assassination attempt.

It was unclear whether Mr. Samhadana or Mr. Abu Shbak would retain ultimate control of the security forces, though any dispute would be resolved in the National Security Council, headed by Mr. Abbas.

Mr. Abbas directly controls the presidential security unit, the border police, and the various intelligence services. The preventive security, which is in charge criminal intelligence, the civil defense, which deals with disasters, and the police fall under the Interior Ministry.

Speaking at a mosque in Gaza City, Mr. Siyam pledged a major crackdown on crime throughout the Palestinian Arab areas.

“We are going to beat with an iron fist all the people and the groups who are acting illegally,” Mr. Siyam said. He said he was referring to crime, not armed resistance against Israel.

Israel, America, and European Union have cut off much of the funding that has kept the Palestinian Authority afloat, labeling Hamas a terror organization and refusing to deal with the new government. Hamas has sent dozens of suicide bombers into Israel, and while it has largely observed a truce over the past year, Hamas officials defended a suicide bombing by another group on Monday that killed nine people in Tel Aviv.

The financial crunch is being felt keenly by 165,000 salaried public sector workers, who have not been paid for last month. The Palestinian finance minister, Omar Abdel Razek, told the AP he doesn’t know where the money will come from or when.

“I have a strange feeling. For the first time, I find myself in such a dilemma,” he said in an interview yesterday. “But I hope that God will provide a solution.”

In the two months between the election and Hamas’s assumption of power, the outgoing government of the defeated Fatah Party hired 9,000 more employees, he said. The number of security officers has risen to 80,000, from the 60,000 reported by the last government, he said.

The Palestinian Authority needs about $160 million every month – $118 million for the payroll and $40 million in operating costs, he said. The government has about $30 million in monthly income, but that money is being spent on the most crucial ministries – health and social welfare.