Rome, July 19 - President Sergio Mattarella said on the 26th anniversary of the Mafia murder of anti-mafia prosecutor Paolo Borsellino Thursday that "honouring the memory of magistrate Borsellino and the persons escorting him also means not stopping to seek the truth on that massacre". "26 years on," said Mattarella, "the memories and emotion for the cowardly attack in Via d'Amelio (In Palermo) are still alive". "Magistrate Paolo Borsellino lost his life along with agents Agostino Catalano, Walter Eddie Cosina, Vincenzo Li Muli, Emanuela Loi and Claudio Traina. "Borsellino was an exemplary magistrate: principled, reserved, brave and determined. "His investigations constituted milestones in the fight against the mafia in Sicily. "Together with his friend and colleague Giovanni Falcone, Borsellino became, fully, the symbol of an Italy that fights and does not surrender to organised crime". Premier Giuseppe Conte also said it was a "duty" to seek the truth about the murders of Borsellino and his five police escorts. "Paolo Borsellino, Agostino Catalano, Emanuela Loi, Vincenzo Li Muli, Walter Cosina and Claudio Traina. Let's cultivate their memory in the daily fight against the mafias," the premier said. "The search for the truth on Via D'Amelio is a duty for Italy which believes in their example and in honesty #July19," Conte said. Italy must continue to fight Mafia "scumbags" to honour the Borsellino's memory, Interior Minister Matteo Salvini said. "The best way to honour the memory of Paolo Borsellino and all the victims of the mafia is to fight with ever more force these scumbags," Salvini said. Falcone was killed by a massive bomb under the Palermo-Palermo Airport highway, along with his three bodyguards and his wife, Italian magistrate Francesca Morvillo, on May 23, 1992. On July 19 that year, two months later, another huge Cosa Nostra bomb killed Borsellino outside his mother's home in Palermo, along with his police escorts. Cosa Nostra bosses including the late Salvatore Totò Riina and Bernardo Provenzano as well as Giovanni Brusca have been condemned for the killings, part of a Mafia reign of terror when members of Italian institutions instituted tough prison conditions, Italian prosecutors have said. One of the mysteries linked to the Borsellino slaying is the disappearance of a bag containing his personal diary, investigative sources say. Prosecutors are still trying to establish who stole it and what exactly it contained. There is also the shadow of alleged State-mafia talks over the two bomb slayings of Falcone and Borsellino. Prosecutors said Thursday that those negotiations "accelerated" Riina's decision to assassinate Borsellino. Earlier this week Sicilian prosecutors called the investigation into the Borsellino killing "the biggest cover-up in Italian history". Magistrates' union ANM said Thursday it would not "squander the legacy" of Borsellino in combating the Mob. The mafia over time has become "less violent but more pervasive" in society, ANM chief Francesco Minisci said in Palermo.