The killings of two close associates of a jailed mobster 11 weeks apart confirmed Montreal's fears that the return of a reputed mafia don has unleashed an underworld power struggle and settling of scores.
The men killed were mobster Raynald Desjardins' associates, and the returned don, fresh out of a US prison, is Vito Rizzuto.
A former ally of the Rizzuto clan, Desjardins betrayed them in a bid for gangland control, mafia experts say.
Desjardins' former brother-in-law and business partner, Gaetan Gosselin, was walking home last Tuesday night north of Montreal when one or more assailants opened fire, killing him. The ambush was reminiscent of one in November where Joseph Di Maulo - also a brother-in-law of Desjardins - was gunned down in the driveway of his home.
The two murders - as well as the killings of a few of the mob's minor henchmen - occurred soon after Rizzuto's October return to Canada, following a six-year term in a US prison for his role in the 1981 murders of three members of New York's Bonanno crime family.
As head of Montreal's mafia for a quarter of a century before his arrest, Rizzuto led with flair and brutality an underworld empire that included lucrative trafficking of Colombian cocaine in Canada and the US.
During his incarceration, however, his Sicilian clan's gangland grip was diminished by new rivals and the Rizzuto family was decimated in its fight to hold on to power.
In December 2009, Rizzuto's son Nick was gunned down on a Montreal street in broad daylight. Ten months later, his elderly father Nicolo was shot dead through a window in his home.
Meanwhile, Rizzuto's brother-in-law and confidant Paolo Renda had gone missing in May 2010; most believe he was killed, but a body has never been found.
A settling of scores is now inevitable. The events of recent months "aim to re-establish a balance" that shifted with the massacre of Rizzuto's clan members during his absence, crime expert Antonio Nicaso said.
Desjardins is presumed safe in a Canadian prison awaiting trial for the murder of rival Salvatore Montagna, whose bullet-riddled body was fished out of the L'Assomption River northeast of Montreal in November 2011.
But Andre Cedilot, co-author of a book on the Montreal mob, believes that more reprisals will come, with six or seven who are "loyal to Desjardins or traitors in the eyes of Rizzuto" likely to be targeted.
Keeping a low profile since his release from prison, Rizzuto, 66, travelled last week to the Dominican Republic apparently for a holiday.
But given recent developments, mafia experts do not believe that he will abandon a life of crime to retire in the sun.
"He'll be back," said Nicaso. "He can't wage a war from afar if he wants to retake control of Montreal."
Should Rizzuto return, however, he and his illicit dealings will face a new level of scrutiny as he has been summoned to testify at a corruption inquiry.
The commission headed by Quebec Superior Court Justice France Charbonneau is investigating alleged graft, bid-rigging and kickbacks in the awarding of government construction contracts in the Canadian province. Witnesses have testified that construction executives colluded with crooked bureaucrats and politicians in a mafia scheme to embezzle public funds.
Federal police surveillance videotapes and wiretaps showed executives handing over stacks of cash to Rizzuto's father, and mobsters using threats to steer the bidding for public works contracts.
The Rizzutos received a 2.5 per cent cut of all public works contracts in the province of Quebec, the commission heard.
A former construction magnate has also testified that Rizzuto himself once mediated a conflict between construction executives for a Transport Quebec contract.
"The mafia isn't just involved in extortion and drug trafficking," said Nicaso. "It's infiltrated politics and finance, too."