INDIANAPOLIS, AUG. 15 -- Tensions remained high and tight security was in evidence at the Pan American Games today as officials vowed to protect athletes and spectators alike in the aftermath of a brawl Friday night when several Cuban boxers charged into the stands.

Two men were injured when members of the Cuban delegation and boxing team became involved in a fistfight at the Indianapolis Convention Center. It remained unclear which group provoked the fight, the Cuban delegation or a group of anti-Castro demonstrators in the stands.

The brawl was the second violent incident at the Games. Last Sunday a fight erupted between the Cuban delegation and protesters after a baseball game.

Local authorities, including Indianapolis Police Chief Paul Anee, had pledged to prevent any further incidents and renewed that pledge today. No charges were filed and there were no new official protests, although police continued to interview witnesses.

Some witnesses blamed Cuban security police for initiating the brawl, while others said the delegation was attacked without provocation by a group believed to belong to the Movement for an Independent and Democratic Cuba (CID), a Miami-based organization.

The spectators tore up and stomped on a Cuban flag while yelling in the stands. Members of the Cuban delegation rushed into the bleachers, and boxer Pablo Romero, a world champion at 178 pounds who had fought the previous night, was seen throwing punches.

The two injured men, who were treated for abrasions to the face, were identifed as Felix Toledo, 45, and Pedro Tamayo, 43, both Miami residents and both believed to be affiliated with CID, according to authorities.

Members of the Cuban delegation have said they will respond to insults and attacks by protesters, which has put local authorities in an awkward position, caught between two political groups. That raised the question of protecting rights of spectators as well as athletes.

Local and Pan Am officials are trying to convince the Cuban delegation to leave security matters to the police, said local organizing president Mark Miles, who talked to Manuel Gonzalez Guerra, head of the Cuban Olympic Committee, following the incident.

"He was remarkably calm and almost reflective," Miles said. "These people believe they were attacked and responded to a physical attack. We'll never know exactly what happened. Our police have tried to explain to them that when there is a problem, to let the police solve it."

One member of the Cuban delegation, Julio Mena, said Friday night after the fight that, "They began to insult us and our revolution. We are not going to tolerate that. We will respond to all provocations."

Guerra said, "We will strike back blow by blow in the face of any aggression whatsoever. I am indignant because of those provocateurs who came to insult us while we came only to compete. Every time a Cuban is attacked, we will strike back. We are not Jesus Christ so we won't turn the other cheek."

Robert Helmick, president of the U.S. Olympic Committee, met this morning with Raul Villaneuva, technical chief of the Cuban delegation. He said the Cuban officials consider this strictly a matter between them and the anti-Castro groups, and that no animosity has been expressed toward organizers or U.S. delegates.

In another development, the Associated Press reported today that U.S. boxers almost came to blows with their Cuban counterparts after words were exchanged outside the ring Friday night.

American super heavyweight Riddick Bowe said today that members of the U.S. team were walking by Cuban super heavyweight Jorge Gonzales and 125-pounder Arnaldo Mesa when one of the U.S. fighters gestured to Mesa by running his finger across his throat in a cutting motion.

Bowe is scheduled to fight Gonzales on Wednesday. Bowe said words were exchanged but Cuban fighters eventually backed off. "He {Mesa} anticipated he wanted to fight but he was able to maintain his composure," he said.

Security will undoubtedly be tight at Sunday night's boxing match, when Kelcie Banks is scheduled to meet Mesa in a quarterfinal. Romero is scheduled to fight Andrew Maynard of Cheverly, Md., in a semifinal bout Wednesday.