“We’re at the limit,” said restaurateur Giulliano Lopresti, who reopened his Argentine restaurant Quebracho on Monday.

Eating lunch at Quebracho, accountant Carlos Weinberger said restaurants should be allowed to open.

The grill sits about six inches above a bed of hardwood quebracho coals that pulse with an orange heartbeat.

Jaime Stiuso, a former high-ranking counterintelligence official who left the country shortly after Nisman’s death, last week told Criminal Judge Fabiana Palmaghini that the prosecutor stood in the way of Argentine-Iranian nuclear collaboration pushed by Venezuelan President Hugo Chavez and that Quebracho — a leftist group with ties to the Fernandez administration, Caracas and Tehran — likely assassinated him.

Quebracho, a left-wing group whose leader, Fernando Esteche, has also been charged by Mr. Pollicita, echoed the sentiment in posters distributed in downtown Buenos Aires.