PORT-AU-PRINCE, Haiti -- Kidnappers came for Petit-Frère Desilus in the early afternoon, as he was driving away from his office.

The street was busy and he was just 10 feet outside the gated compound where he worked as a billing clerk. But they got him anyway, Desilus recalled recently in a hushed voice, trying to steady his trembling hands.

Two young men, their faces hard but calm, flashed pistols at him. When he turned, he saw four more gun barrels behind him. Pedestrians did nothing, merely swerving around the unfolding scene, he said.

"Lie down, shut up," Desilus remembers being told. "Today you're going to get yours."

Pressed flat against the back seat, Desilus was about to begin a downward spiral that severed his tenuous hold on a working-class lifestyle, leaving him poor and depressed more than four months after his captors released him. His troubles have become commonplace here. One year after a presidential election that generated optimism and marked only the second peaceful handover of power in Haitian history, Port-au-Prince is a city of fear.

Despite the presence of thousands of U.N. troops and a new military offensive to root out gangs, armed thugs still rule much of this hilly capital, where many of the 2 million residents live in tin or cinder-block shacks. A swarm of recent kidnappings is terrorizing residents and scaring away foreign investment.

Dozens of schools closed in December after students were kidnapped in a series of incidents and a school bus was hijacked. That month, at least 100 people were reported kidnapped, the most since August, when 115 were abducted. Victim advocates say the real numbers may be much higher; once freed, people often are afraid to go to the police.

Haiti's government has been powerless to stop the crisis. International advisers describe the police force and judicial system as critically dysfunctional and profoundly corrupt.

"We are a failed state -- our institutions are bad, they don't work," said Kesner F. Pharel, a Haitian economist who was trained in the United States and runs a business consulting firm in Port-au-Prince. "It is crucial for Haiti to solve the security problem if we have any hope of making progress."

The kidnapping plague, which began in 2004 after the ouster of President Jean-Bertrand Aristide and peaked during the past six months, is the latest horror in a long history of upheaval that has sealed Haiti's position as the Western Hemisphere's poorest nation. A hip destination for the adventurous rich in the 1970s -- a place where Mick Jagger of the Rolling Stones hung out and where tourists lounged at the Club Med -- Haiti is now a barely functioning country, dependent on the largess of international donors for two-thirds of its budget. The United States, which provides $200 million a year, is Haiti's largest bilateral donor.

Decades of coups and political instability have ruined Haiti's economy and tourism industry, leaving factories closed and once-thriving beach resorts abandoned. According to the International Monetary Fund, 76 percent of Haitians live on less than $2 per day and 55 percent of those live on less than 44 cents a day.

Many here had hoped for stabilization after the election last February of President René Préval, a soft-spoken agronomist who held the presidency from 1996 to 2001 and who promised reconciliation among 100 political parties. But crime has soared under Préval, exacting its heaviest toll on the poor and working class, who cannot afford ransoms or the bodyguards and bulletproof vehicles that shield every movement of Haiti's entrenched elite.

Desilus, 42, a slender man with big, sad eyes, was far from joining Haiti's elites. But he had scratched his way out of the slums and gotten a decent job. Before being kidnapped, he had managed to buy a tiny one-room apartment, where he lived with his wife and three of his six children.

The kidnappers, he said, took him to Cite Soleil, a 2 1/2 -square-mile seaside slum of more than 200,000 people that is ruled by gangs. The kidnappers beat him inside a second-story room that had been converted into a makeshift cell with heavy bars on the windows. They made him drink his own urine, he said.

Following a practice typical of kidnappers here, Desilus's abductors called all the numbers stored in the address book of his cellphone, each time threatening to kill him and demanding $100,000, the equivalent of 20 years' salary for Desilus. A day later, they settled for $4,800 and released him. But his troubles were just starting.

Traumatized by the experience, he asked his boss to let him switch to a job that would require moving around the city less. His boss responded by firing him.

Meanwhile, the friends and associates who had paid for Desilus's ransom were pushing to get their money back. Desilus said he sold his little apartment, as well as a small plot of land that he owned in the country, to pay off his debt. He drained his bank account.

Suddenly homeless, he was forced to move his family into a cousin's home. Jobless, he had to pull four of his children out of school, as even Haitian public schools charge tuition and require parents to buy materials.

"For me to build up what I had, it took me 10 years," he said. "I have to start all over. But being in this country, I don't see how I can."

Desilus desperately wanted someone to face justice. He tried repeatedly to get the Haitian police interested in his case. But each time the officers refused to write a report, he said.

It was a futile exercise that another kidnapping victim, a music vendor who goes by the nickname "Peaceful Michel," didn't even consider embarking upon. Michel, who was abducted in December, was seized in front of a police station and said he is certain the officers witnessed the kidnapping. Friends who have also been kidnapped told him they were "just laughed at" by police when they tried to file complaints, he said.

"Unless you're a millionaire, they're not listening to you," said Michel, who was deported from the United States after serving a four-year drug sentence and now is active in organizations that try to aid Haitian deportees.

The United Nations, which is engaged in background checks of police that officials believe could lead to the dismissal of 1,000 corrupt officers, is now overseeing the largest military operation to defeat gangs since being deployed here in 2004. U.N. officials hope to stem the flow of kidnap ransoms to gangs, some of which need as much as $70,000 a month to pay for their operations.

Préval initially opposed military intervention, opting to negotiate with the gangs, and invited several top gang leaders to the National Palace. Edmond Mulet, the U.N. special envoy to Haiti, described the talks as a "very strange" strategy.

"By mid-September Préval said, 'This is going to work. This will be over by October,' " Mulet recalled during an interview at his headquarters in the Hotel Christopher in Port-au-Prince. "I said, 'Okay, if you say so.' But I knew in my heart it would not work."

In the past year, kidnappers appear to have been targeting victims throughout the city rather than staying in the slums that are patrolled by the U.N. troops. Residents of neighborhoods once considered safe now feel anxious.

Christian Duvivier was nabbed after leaving Magdoo's, a hip hangout for Port-au-Prince's young, moneyed set in the prestigious hilltop neighborhood, Petionville.

Kidnappers rammed their car into Duvivier's vehicle, he recalled in an e-mail from the Dominican Republic, where he fled after a ransom was paid and he was released. They pulled out guns and told him they were "the devil's sons" and that "they kill for fun," Duvivier said.

Young people and professionals are pouring out of Haiti. By some estimates as many as 50,000 have left in the past several years, creating a massive "brain drain," according to Pharel, the economist.

But for some kidnapping victims, fleeing is not an option. Emmanuelle Poncet, a Port-au-Prince math teacher, has spent the five months since his kidnapping and release trying to get a visa to enter the United States so he can leave Haiti and "never come back." He finds his solace in chain-smoking and bottles of rum, a form of self-medication that he knows is ruining his health.

Poncet's brother, a Catholic priest, and a group of friends paid nearly $14,000 to free him. Like Desilus, Poncet has sold what little he had to pay off his debts. His car and a small farm were gone within days of his release, sold cheap because the buyers knew he was desperate.

One week after his release, Poncet got a phone call from another group of kidnappers. They were holding his brother-in-law, they told him. And they wanted money.