At nightfall the crowd, which had started small, grew quickly as thousands marched from work directly to the plaza.
The little clusters of arguing protesters dissolved into a chanting, jumping mass. A nucleus of followers of the late president Juan Peron led the chanting with increasingly imaginative--and insulting--slogans, but the police did not immediately move in.
"Listen, they're shouting that Galtieri is a son of a b----," said a police officer indignantly.
"I know," shrugged his partner, "but it's true."
Soon the crowd began throwing coins. Devaluated 100 peso coins were used against the police and the press watching from the other side of the police barrier.
Shortly before 7 p.m. (6 p.m. EDT), when Galtieri's appearance on the balcony was considered imminent, demonstrators in the front began setting fire to newspapers carrying the headline "Cease-Fire Agreed." They threw the burning papers at the police.
"Get the tear gas," one policeman yelled to another as he marched a struggling protester to a waiting van. Shortly afterward, the first gas grenades were fired into the crowd, and by 7:15 p.m. the plaza was deserted.
But an hour after the tear-gas attack, smaller groups of demonstrators had returned and were fighting with police. Some set fire to trash cans in front of the cathedral on the plaza and other threw rocks through windows of government buildings.
A government communique released after the initial skirmish said that "the national government's invitation to a meeting in the Plaza de Mayo had a positive response." It added, however, that "a reduced group of activists began to chant obscene and insulting slogans and to start fires. President Galtieri will now address the nation on national television and radio at 9 p.m."