In Cape Breton in the 1920, there were long battles between the miners and the miner owners over wages and living standards. Among other things, as it says in the The Canadian Encyclopedia,
The 1925 strike lasted 5 months and culminated in a bloody battle at Waterford Lake, where coal miner William Davis was killed by company police on 11 June 1925.
Growing up in Glace Bay, Cape Breton, we honoured William Davis annually on Davis Day, decades after the event occured.
It’s some of the things that I thought of when I read about South African Police Fire on Striking Miners in NYTimes.com. The South African tragedy was much worse, with 18 miners dead.
I hope cooler heads prevail and that the miners get much better treatment. There is nothing that can be done to reverse the terrible death of the miners, but there should be great efforts made to comfort and compensate the families of them, not to mention changes put in place to prevent this from happening again.
Mining is tough enough underground. Above ground, it should not be tougher.
Smart People I Know 
at least, back in the day, the miners were not held criminally liable for the murderous acts of the cops/security force. The best part of the Battle of New Waterford lake, for me, was how the people took the murderous thugs hired by the mine and the Government of Canada to the jail. They believed in justice on that day, and that is what makes me so proud of our shared history. I hope we can be as brave and as committed to justice today