BUENOS AIRES — In what may be a breakthrough in the case, Argentine police have arrested 15 people in connection with the 1994 bombing of the Jewish communal headquarters here.

Among those arrested Friday of last week were eight members of the army who, along with the other detainees, were said to have links to terrorist groups.

Judge Juan Jose Galeano, the official in charge of the investigation of the bombing of the Argentine Jewish Mutual Aid Association, ordered more than 50 searches in several areas of Greater Buenos Aires, including the Campo de Mayo army base, the largest in Argentina.

Galeano said that he was pursuing a new "avenue of investigation" in an attempt to establish the source of the explosives used in the bombing, which left 86 dead and at least 300 wounded on July 18, 1994.

All those arrested are experts in explosives and were linked to Carlos Alberto Telleldin, the sole suspect held until now in connection with the case. He was charged with selling the Renault van allegedly used in the bombing.

A source close to the investigation said the latest arrests "might be a major breakthrough, a step in the right direction, the key to find who gave support to the bombers."

Police Commissioner Angel Salguero, the official who conducted the searches, said the group now under arrest "combines different elements: extreme rightists, drug dealers and traffickers of assault weapons. They are linked to other groups capable of terrorism."

During the searches, the police found 75 hand grenades, 110 detonation caps, seven rocket-propelled grenades, 60 blocks of plastic explosives, handguns and more than two pounds of marijuana.

One of the suspects was found in possession of a set of false IDs, including fake police badges and judiciary officials' badges.

Jewish leaders have complained about what they describe as the slow pace of the investigation, which has to date provided no satisfactory explanation for the attack.

A March 1992 attack on the Israeli Embassy in Buenos Aires also remains unsolved. That car bombing killed 29 people and left more than 100 injured.