I have found the old Guardian showing the event in our archives (SHGV) and the murder ocurred on the 26th of October 1963 during supper time. Mr Yvon Tousignant, the owner of Tousignant & Frere crossed the street to the Banque de Montréal to make his deposit and was confronted by the hoods. Mr Tousignant resisted and was shot. The businessman who owned the A. Normandin shoe store next door, Mr Roger Séguin came to his aid and he died later at the Verdun General Hospital. Six suspects were picked up in Toronto, 4 men and 2 woman. Amongst them were John Spencer 25, and Robert Terence Hawley 24 of Verdun. Both escaped from the Verdun Protestant Hospital.
Article in the 9th of January 1964 Guardian:
Robert Moran, 30 years old auto salesman who was the last of six persons arrested in connection with the murder of Yvon Tousignant, Wellington street grocer who was slain last October 26th was sent to trial at the next session of the court of Queen's Bench by judge Armand Cloutier on a capital murder charge. No defence was offered by his lawyer Real Gagnon at the appearance for voluntary statement. Two other men, alleged companions of Moran at the time of the murder have been sent to trial on the same charge. They are: John Allan Thompson 25 and Robert Hawley 26, who have been charged with capital murder.
I had to take the enclosed photos with my camera as the Guardians are in a bound book and are too large to put on the scanner. The quality is hazy but I will see if I can improve on this on my next trip to Verdun and come up with more details.