Nurses and volunteers watch over drug users at the Toronto's first pop-up supervised drug-use site. In the month since the site started operating in a gritty east-end park with the tacit approval of police and city officials, volunteers have stopped 27 overdoses. The activists behind the site, who call themselves the Toronto Harm Reduction Alliance, say it's a desperately needed response to the rising wave of opioid overdose deaths caused by the increasing presence of fentanyl in other street drugs. The mayor and city officials do not want it to become a permanent fixture in the park.