Sporadic bursts of gunfire rang out Thursday as hundreds of U.N. troops and police surrounded a teeming seaside city in advance of an offensive aimed at disarming street gangs and restoring order to Haiti's violent capital ahead of fall elections, officials said.

The operation in Cite Soleil (search), a crowded slum that is built on landfill from Port-au-Prince and borders the capital, comes amid surging violence that has killed hundreds since September, and follows recent clashes in the countryside that left two peacekeepers and two ex-soldiers dead.

Criticized for inaction, leaders of the U.N. mission have pledged to crack down on armed groups in this volatile Caribbean nation.

In Cite Soleil, repeated bursts of gunfire were heard and armed men fired at a car carrying an American freelance photographer and her driver. A bullet entered the vehicle but no one was injured.

Associated Press reporters saw U.N. peacekeepers (search) racing toward the sound of gunshots, firing their rifles into the air, but it appeared the offensive into Cite Soleil had not begun. There were no reports of injuries.

More than 1,000 Jordanian troops and Chinese and Haitian police cordoned off the shantytown of metal-and-wood shacks and trash-strewn streets, said Lt. Col. Elouafi Boulbars, a U.N. military spokesman. The soldiers set up road blocks and began searching cars and residents for illegal weapons.

"This is the first stage. Then we'll enter the community," Boulbars said, adding that no clashes have been reported yet.

"We will respond appropriately if our soldiers come under fire," he said. "But the structure of this ghetto makes it very difficult to penetrate because of the risk of collateral damage. That's our main concern."

The operation comes as Haiti's caretaker government and a 7,400-member U.N. force struggle to contain flashpoints of violence more than a year after an uprising ousted President Jean-Bertrand Aristide (search). More than 400 people were killed in September in clashes between police, peacekeepers, pro- and anti-Aristide gangs and former soldiers who led the February 2004 revolt. At least 40 police officers have been killed.

U.N. and interim officials fear more violence could disrupt elections in October and November. Boulbars said soldiers and police would plan to sweep the area for illegal guns in an operation that could last days. He said operations in other communities will begin shortly.

Late Wednesday, clashes between rival gangs left several people dead, including a powerful anti-Aristide gang leader known as "Labaniere," Boulbars said.

Separately, unknown assailants shot at a Filipino soldier guarding the U.N.'s new headquarters in Port-au-Prince early Thursday, Boulbars said. The soldier escaped injury because the shots hit him in his helmet and protective vest.

Earlier this month, U.N. troops fought bands of armed ex-soldiers in two rural towns that left two peacekeepers dead — the first fatalities among troops since the U.N. force arrived in June 2004. Two ex-soldiers also died.

Interim Prime Minister Gerard Latortue on Wednesday criticized an arms embargo on Haiti that he said was hurting the country's ill-equipped police force to curb violence. While Latortue did not mention specific countries, the United States imposed an arms embargo on Haiti in 1991 after a military coup first ousted Aristide. A U.S.-led military intervention restored Aristide in 1994 but maintained the embargo.

The State Department has previously said it will consider approving individual requests for weapons. U.S. officials did not immediately return calls seeking comment.

"I'm announcing to the international community that my patience has run out," Latortue told reporters. "The population is asking for security while we are sending our police to the slaughterhouse."