FORT BENNING, Georgia (CNN) -- Thousands of demonstrators gathered
                  Sunday in the largest-ever protest against the U.S. Army's School of the
                  Americas, a military training center which opponents say turns out a
                  steady stream of Latin American dictators, torturers and rogues.

                  The demonstration has been staged annually since 1990 to protest what
                  participants call the "School of Assassins." They say Latin American
                  graduates use what they have learned at the school to violate human rights in
                  their homelands.

                  Army officers say the school has helped advance democracy in Latin
                  America and that it has reformed its curriculum to stress respect for human
                  rights.

                  Actor Martin Sheen was among those who addressed the protesters, many
                  of whom carried white crosses they said represented victims of some of
                  the school's almost 60,000 graduates.

                  "We honor our Army, we respect their mission, but this is not part of
                  that mission. This is an embarrassment to the Army," Sheen said.

                  Some protesters marched onto the grounds of the U.S. Army's Fort
                  Benning, which has housed the school since it moved from Panama in 1984.

                  According to Columbus police officer Frances McDaniel, the protesters
                  offered little resistance when they were placed on buses, driven out and
                  dropped off on city property

                  No one was arrested, McDaniel said. But past protests have resulted in
                  arrests and jail terms. Federal courts have ruled that military installations can
                  restrict political and partisan demonstrations.

                  Organizers estimated the crowds at 7,000; Columbus police spokesman Lt.
                  M.C. Todd put the figure at fewer than 2,500.

                  Legislative efforts unsuccessful

                  U.S. Rep. Joseph P. Kennedy II of Massachusetts is among those who have
                  complained about the School of Americas, located about 85 miles southwest
                  of Atlanta. Opponents in Congress have tried without success to cut funding
                  for the school.

                  Graduates of the school include former Panamanian strongman Manuel
                  Noriega, former Argentine dictator Leopoldo Galtieri, Haitian coup leader
                  Raoul Cedras and the late Salvadoran death squad organizer Roberto
                  D'Aubuisson.

                  The gathering was larger than eight previous annual protests, which mark
                  the anniversary of the November 16, 1989, killings of six Jesuit priests by a
                  Salvadoran army unit. The school trained 19 of the 26 soldiers
                  implicated in the deaths by a U.N. investigation.

                  "We gather here to honor our brothers and sisters in Latin America,"
                  the Rev. Roy Bourgeois, a protest leader, told supporters. "We will close
                  the School of the Americas."

                  More than 600 of the roughly 2,000 demonstrators last year were arrested
                  when they entered the military post.

                  About three dozen people who had been arrested for previous protests
                  were convicted of criminal trespass earlier this year and sentenced to six
                  months in prison and fined $3,000 each.

                  Fort Benning officials held a debate about the school Saturday, but
                  opponents declined to participate when they were told they could not carry
                  cardboard coffins onto the buses that would transport them to the event.

                                 Reuters contributed to this report.