Declaring Gaza "open for business," Commerce Secretary Ron Brown brought American investors to the autonomous area Tuesday to meet with Palestinian business leaders.

"We are bringing together a public-private partnership," Brown said in a joint appearance with PLO chief Yasser Arafat. Brown acknowledged the difficulty of "starting from zero."Arafat said the Palestinians need help building infrastructure in the autonomous regions.

"We are sure this coordination and cooperation can do a lot for our people, for the peace process and for our children," he said.

Private investment is a small part of the foreign money the Palestinians need to relieve the poverty that has driven some Palestinians into the camp of radical Muslim fundamentalists who oppose peace with Israel.

The American government has pledged about $500 million over five years as part of the worldwide aid package of $2.4 billion for the Palestinians.

Several million dollars in American aid have trickled in for Gaza housing projects, but foreign donors are withholding the bulk of the money until Arafat establishes new accounting procedures.

Brown has called in the past for private investment in the Palestinian self-rule zones. But officials traveling with the secretary said that since autonomy began in May in the Gaza Strip and West Bank town of Jericho, only one private U.S.-Palestinian venture has been formed, a factory making building materials in Gaza.

The U.S. government offers private investors loan guarantees and political risk insurance as incentives.

Brown said peace hinges on economic stability.

Meanwhile, Palestinian police rounded up 45 followers of a radical Damascus-based group Tuesday following a deadly ambush on Israelis, and Arafat swore not to let anyone spoil his peace pact with Israel.

Arafat has been under mounting pressure from Israel to crack down on militants and foil attacks on Israelis. On Monday, gunmen killed one private Israeli security guard and wounded another as the two men escorted Israeli gasoline trucks into Gaza.

The Democratic Front for the Liberation of Palestine, a radical Palestine Liberation Organization faction based in Syria, claimed responsibility for the attack, intended to embarrass Arafat and sabotage Israel-PLO autonomy talks.

Arafat said he would take action against militants opposed to the peace process.