A month after Abdirahman Abdi died following a violent police altercation in Ottawa, Canada, Black Lives Matter is staging protests across the country in a call for justice for a man it says was "killed because he teetered on the dangerous intersections of Blackness, Somaliness, Islamophobia, and mental health."It's the latest action by the US-created movement's Canadian branches, and is its most ambitious protest to date. The most visible demonstration on Wednesday unfurled outside Toronto, where activists staged a blockade at the Mississauga headquarters of the Special Investigations Unit, Ontario's police watchdog.Rallies and letter-writing campaigns are also set for Ottawa, Hamilton, Kitchener, Edmonton, and Winnipeg, although not all are being organized by BLM.Abdi, a 37-year-old man believed to have mental-health issues, died on July 24 in an Ottawa hospital after sustaining injuries from two police officers. That morning, police received calls about an incident at a coffee shop in the Hintonburg neighborhood in Ottawa, though a witness at the cafe said the alleged groping never happened. Police officers arrived at the area, chased Abdi, and according to witnesses, then pepper-sprayed him and hit him with batons, punches, and kicks. They then allegedly left him lying handcuffed, facedown on the concrete, for several minutes without performing CPR. The investigation into Abdi's death has not yet concluded, but an official Black Lives Matter Facebook event page for the protest claims, "The SIU works to protect the Police. The SIU is not accountable to our communities." The SIU is responsible for investigating police incidents leading to death or serious injury across the province, including Abdi's case. Rarely do its investigations result in the convictions of police officers. The event page cites as evidence the fact that SIU cleared police of wrongdoing in several other incidents involving a citizen being killed, including Andrew Loku and Jermaine Carby. On the morning of August 15, Black Lives Matter Toronto—which gained national attention earlier this summer for a protest at Toronto's Pride Parade—shut down the busy Yonge-Dundas intersection in the city's core for a short period of time. The group gave a press conference from the middle of the intersection, in which they announced a list of demands targeted at a range of subjects, including the SIU, Ottawa Police Service, and the hospital where Abdi died. "For over 24 hours, they claimed, to his family and the public, that he was alive and in critical condition, even though he was dead 45 minutes before arriving at the hospital," Black Lives Matter Toronto co-founder Rodney Diverlus said at a press conference. "This is unbelievable!" Another demand is that the Ontario College of Physicians and Surgeons should "strip the license of the health practitioner(s) who authorized the withholding of information regarding Abdirahman Abdi." The group alleges the SIU collaborated with the hospital and the police in order to keep Abdi's death from the public. A former deputy chief of police in Ottawa, Larry Hill, told CBC News that the SIU will likely not investigate race as a factor in Abdi's death. Follow Davide Mastracci onTwitter.