The Summit of the Americas has gone into overtime, as delegations from 34 countries seek common ground on such controversial issues as free trade, and the best way to combat poverty.
Hours after the schedule called for closing ceremonies, the delegations were still meeting behind closed doors.
They are trying to bridge a deep gap over proposed negotiations on a hemispheric free trade zone.
Twenty-nine of the 34 countries attending the summit support the idea, but some of the biggest nations in South America do not. They include Brazil, Venezuela and Argentina.
President Bush has been pushing the concept of a free trade zone from Alaska to the southern tip of Argentina.
He attended the first three hours of extended talks here Saturday in Mar del Plata, and then left for a scheduled visit to Brazil, leaving Tom Shannon, the Assistant Secretary of State for Western Hemispheric Affairs to represent the United States.
The summit was marred Friday by violent protests that resulted in serious property damage and dozens of arrests.
However, when the delegates began their lengthy closing session, the city was calm, and clean-up efforts were well underway.
Dozens of Argentine business owners returned to a scene of utter destruction in the resort town of Mar del Plata Saturday.
A day earlier, protests turned violent blocks away from where President Bush and other leaders were gathered for the 34-nation Summit of the Americas.
Local residents, many of whom had feared such an outbreak of violence, are deeply saddened, dismayed and angry.
One day after scores of masked youths went on a rampage near barricades that formed a security perimeter for the Summit of the Americas, business owners and employees were sweeping up huge mounds of broken glass and debris.
Inside a bank, blackened by fire, an automated teller machine was barely recognizable, its outer casing melted into an odd shape.
Passersby shook their heads in disbelief. Rotisserie chicken vendor Mario Maurino says he and a younger female employee were trapped inside, when club-wielding youths smashed his store’s front windows late Friday.
He says, "It was as if I were Public Enemy Number One - I, who come to work and never take a day off. And I felt completely exposed and unprotected. That was the sensation, and I assure you, it is terrifying to feel alone, completely alone."
Mr. Maurino says he fell victim to vandals and delinquents, and does not believe those who smashed his chicken shop were the same people who marched peacefully against President Bush earlier in the day.
Asked if he blames President Bush in any way for his misfortune, he waves his hand dismissively.
He says, "No, no, not at all. How could Bush be at fault? He had to come to the summit."
Instead, Mr. Maurino blames Argentine security forces, who he says were slow to respond to the situation, as well as Argentine officials, whom he described as incompetent.
He says the troublemakers had free reign of the streets for more than half-an-hour before police arrived on the scene.
Other merchants have made similar complaints, and a local business group says it will petition Argentina's government for reparations. Mar del Plata's mayor has said he will actively support any legal action taken to secure compensation.
The mayhem was concentrated along six city blocks, less than a kilometer away from where leaders at the Summit of the Americas had gathered for a gala dinner.
Aside from destroying and looting property, masked assailants hurled rocks and sticks at security forces, who stood their ground behind four-meter high barricades.
Riot police fired tear gas, and eventually cleared the affected area, making dozens of arrests in the process. No life-threatening injuries were reported.
But intense sorrow is felt in this seaside town, Argentina's number-one domestic tourist destination, known for magnificent beaches, vibrant nightlife and, until now, tranquil repose.
In the middle of Friday's melee, a distraught pharmacy owner, hoarse from shouting, pleaded with rampaging youths to spare her business.
She said, "Boys, not the pharmacy! This is a pharmacy of Mar del Plata, which has nothing to do with the summit. We are all against President Bush, but please do not punish my people, my city." Her plea was in vain.