The Associated Press

In this Saturday, June 27, 2009 photo, former lightweight boxing world champion Alexis Arguello, right, of Nicaragua, talks with Jose Aponte, the mayor of Carolina, Puerto Rico, during an inauguration of a public boxing gymnasium named after Arguello, in Carolina, Puerto Rico. Arguello, who was also the current mayor of the Nicaraguan capital Managua, was found dead in his Managua home on Wednesday, July 1. (AP Photo/Anthony Luna)

MANAGUA, Nicaragua — Alexis Arguello, who fought in one of boxing's most classic brawls and reigned supreme at 130 pounds, was found dead at his home early Wednesday.

Presidential spokeswoman Rosario Murillo confirmed Arguello's death and an autopsy was pending. The La Prensa newspaper reported the Arguello -- elected mayor of Managua last year -- was found with a gunshot wound to the chest.

The 57-year-old Arguello retired in 1995 with a record of 82-8 with 65 knockouts and was a champion in three weight divisions. He was perhaps best known for two thrilling battles with Aaron Pryor and fights with Ray Mancini, Bobby Chacon and Ruben Olivares.

"I'm kind of in a daze right now," Pryor told The Associated Press. "Those were great fights we had. This was a great champion."

Nicknamed "The Explosive Thin Man," Arguello was inducted into the International Boxing Hall of Fame in 1992, where flags were flying at half-staff in his honour Wednesday.

In 1999, a panel of experts assembled by The Associated Press voted Arguello the best junior lightweight and sixth-best lightweight of the 20th century. He never lost a fight at 130 pounds, and his popularity in his own country was so great that he carried the flag for Nicaragua at the Beijing Olympics.

"Not only was he one of the greatest fighters I've ever seen, he was the most intelligent fighter," Bob Arum, who promoted some of his biggest fights, told the AP. "He was a ring tactician. Every move was thought out. And he was a wonderful, wonderful person."

Arguello turned pro in 1968 and lost his first bout. He didn't lose much more, and six years later knocked out Olivares in the 13th round to win the featherweight title.

Arguello went on to win the super featherweight and lightweight titles, his five-foot-10 frame and long reach allowing him to move up in weight without losing his tremendous punching power. At the time, he was only the sixth boxer to win championships in three weight classes, and was considered for a while the best pound-for-pound fighter in the world.

He moved up in weight again in November 1982 to challenge Pryor for the 140-pound belt, a match billed as "Battle of the Champions," and tried to become the first person to win titles in four divisions. More than 23,000 fans packed the Orange Bowl in Miami, and the two waged an epic battle before which Pryor knocked out Arguello in the 14th round.

"It was a brutal, brutal fight," Arum said. "That was something I will never, ever forget as long as I live. That was one of the most memorable fights I ever did."

The bout was named "Fight of the Year" and "Fight of the Decade" by Ring Magazine, but was shrouded by controversy. Pryor's trainer, Panama Lewis, gave him a water bottle after the 13th round that many believe contained an illegal substance -- an accusation Pryor denies.

A rematch was ordered and they met again a year later at Caesars Palace in Las Vegas. This time, Pryor knocked out Arguello in the 10th round.

Arguello was never the same fighter after losing to Pryor. He won a couple more fights, then was out of the ring from 1986 until 1994, when he made an ill-advised comeback. He retired for good the following year.

"Alexis Arguello was a first-class fighter and a first-class gentleman," said Hall of Fame executive director Edward Brophy. "The Hall of Fame joins the boxing community in mourning the loss of a great champion and friend."

Arguello fought against the Sandinista government in the 1980s after it seized his property and bank account, but later joined the party and ran for mayor of the capital last November. He defeated Eduardo Montealegre, though opponents alleged the vote was fraudulent.

Arguello had returned Sunday from Puerto Rico, where he honoured the late baseball Hall of Famer Roberto Clemente. His death prompted Nicaragua President Daniel Ortega to announced he was cancelling a trip to Panama for the inauguration of President-elect Ricardo Martinelli.

"We are upset," said Murillo, whose office declined to provide details about Arguello's death. "This is a heartbreaking announcement. He was the champion of the poor, an example of forgiveness and reconciliation."