"When our friends and neighbours are hurting, we feel it in Ontario," McGuinty said in a statement posted to Twitter. "Our hearts break for Newtown families and the Sandy Hook community."
A gunman killed 26 people, including 20 kids, Friday at Sandy Hook Elementary School in Newtown, Conn. A law enforcement official said the suspect, 20-year-old Adam Lanza, was dead from a self-inflicted gunshot wound and that his mother worked at the school.
Scores of public figures and other people expressed their condolences on social media. In Ontario, political party leaders took to Twitter to say they were shocked and horrified.
"Heart goes out to all affected by tragic shooting in Connecticut today," wrote Progressive Conservative Leader Tim Hudak. "Our thoughts and prayers are (with) the children, staff and their families."
NDP Leader Andrea Horwath wrote that "no words can describe the shock and horror of what happened in CT. Our thoughts go to the whole community as they grapple with this tragedy."
The news also affected law enforcement agencies across the province, as they too reached out through Twitter to express their sympathies for the victims in Connecticut.
"Moment of silence at the Toronto Police Service Board meeting for the shooting victims in Newtown Connecticut," Toronto Deputy Police Chief Peter Sloly tweeted.
Kingston Police wrote on Twitter, "Devastating news. Our prayers and condolences," while police in Guelph also expressed sadness.
"GPS thoughts and prayers go out to the children and adults Killed today in Connecticut Elementary School shooting," Guelph police tweeted.
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