Days later, Minister of Justice, Ernest Lapointe, signed the order that resulted in labeling 31,000 Italian Canadians as "enemy aliens". With habeas corpus suspended, between 1940 and 1943, between 600 and 700 Italian Canadian men were arrested and sent to internment camps as potentially dangerous enemy aliens with alleged fascist connections. While many Italian Canadians had initially supported fascism and Benito Mussolini's regime for its role in enhancing Italy's presence on the world stage, most Italians in Canada did not harbour any ill will against Canada and few remained committed followers of the fascist ideology.
Prior to June 10, 1940, the RCMP began systematic surveillance of Italian Canadian fascists following Mussolini's invasion of Ethiopia in October 1935 and in 1938 published a 60-page report detailing fascist activity in Canada.
Newspaper accounts of the day, such as the Ottawa Citizen, tell that the status of "enemy alien" was immediately placed on non-resident Italians older than 16 years of age, and on Italian Canadians who became British subjects after September 1929. The category later expanded to include nationals of belligerent states naturalized after 1922. Those affected by the War Measures Act and Defense of Canada Regulations (DOCR)  were forced to register with the RCMP and report to them on a monthly basis.
Some of the Italian Canadian men interned at Camp Petawawa had ties to Italian fascist organizations, but many had no political affiliation and were probably interned as a result of mistaken identity or because of false accusations.
On 10 June 1940, all fascist organizations in Canada were deemed illegal. They included the Casa D'Italia consulate on Beverley Street, the fascist newspaper Il Bolletino and the Dopolavoro (after work) social club. Casa D'Italia was seized by the Custodian of Enemy Alien Property and sold to the RCMP.
Toronto Star publisher Joseph E. Atkinson opposed fascism and the Ethiopia campaign, and the paper received a bottle of castor oil in response to an editorial titled, "A Gentlemen's Agreement", sent by a group of fascists.
In 1990, former prime minister Brian Mulroney apologized for the war internment to a Toronto meeting of the National Congress of Italian Canadians: "On behalf of the government and the people of Canada, I offer a full and unqualified apology for the wrongs done to our fellow Canadians of Italian origin during World War II."
In May 2009, Massimo Pacetti introduced bill C-302, an "Act to recognize the injustice that was done to persons of Italian origin through their "enemy alien" designation and internment during the Second World War, and to provide for restitution and promote education on Italian Canadian history [worth $2.5 million]", which was passed by the House of Commons on April 28, 2010. Canada Post was also to issue a commemorative postage stamp commemorating the internment of Italian Canadian citizens, however, Bill C-302 did not pass through the necessary stages to become law.
In 2013, as a part of the permanent exhibition Italian Canadians as Enemy Aliens: Memories of World War II at the Columbus Centre in Toronto, funded by Villa Charities Inc and Citizenship and Immigration Canada, artist Harley Valentine created a monument recognizing the internments called "Riflessi: Italian Canadian Internment Memorial". The main statue is composed of several profiles—a (grand)father, internee, pregnant mother, and child—that combine to form a single figure in mirror polished stainless steel. The multiple profiles represent the full communal trauma that was caused by the locking up of individuals. The commission was to commemorate not only the dark history of internment, but also the perseverance of the Italian–Canadian community to put internment behind them and emerge in the decades following as a cornerstone of modern Canada. To that end, Valentine placed an empty marble plinth facing the statue from the opposite end of a tiled pathway, onto which visitors are able to step and see themselves reflected in the mirrored statue, completing the piece by establishing the present's connection to its past.