Independent tech analyst Carmi Levy said this incident should be "sounding a very loud alarm" for the Canadian government that is failing to take cyber security seriously.
"It's a whole new threat level," Levy said, speaking from London, Ont., on Monday.
"And because Anonymous now seems to be very firmly focused on Canadian targets it's reasonable to assume that Canadians can expect this kind of activity to continue and intensify in the next few weeks and months."
RCMP officers shot and killed a man Thursday evening outside a restaurant in Dawson Creek, B.C., where a hearing for the controversial Site C hydroelectric dam was taking place.
The BC Coroners Service identified the shooting victim as James McIntyre, a 48-year-old Dawson Creek resident.
Police said they shot the man after he refused to comply with officers' instructions.
Eyewitness video posted online showed a man wearing a Guy Fawkes mask lying bloodied on the ground while two Mounties faced him with weapons drawn.
The smiling Fawkes mask has become a symbol for Anonymous. Fawkes was the most well-known member of a plot to blow up the British Parliament in 1605.
The hacktivist group issued a press release claiming the man killed last Thursday as one of their own and vowed revenge against the RCMP. It promised to identify the officer involved and release his personal information on the Internet.
The group claimed responsibility for temporarily disrupting the RCMP's main website and site for its Dawson Creek detachment one day after the shooting.
While Anonymous has issued warnings and interrupted Internet service in the past, Levy said this particular case is different because it didn't take place exclusively in the virtual realm.
"This isn't just an online activity — they're actually claiming that one of their own was killed, which significantly raises the stakes," he said.
Anonymous is relatively benign as far as hacking groups go and wants to be perceived as a power for good, defending the underdog, said Levy.
"(But) we do ourselves a disservice by assuming that Anonymous will always act in support of pure justice," he added. "It's only a matter of time before Anonymous picks another issue of public policy and initiates online action around that one as well — this will never end."
Public Safety Minister Steven Blaney was in Vancouver speaking to the city's board of trade on Monday but did not make himself available to answer questions about the shooting and cyber threats.
A statement issued later from the minister's spokesman Etienne Rainville said that no comment would be made as the matter is under investigation.
B.C.'s Justice Minister Suzanne Anton confirmed there was a cyber threat against the RCMP and expressed concern for the officers involved.
"Police want to keep people safe," she said. "They don't like it when situations like this happen. It's very difficult for everyone."
The province's police watchdog is investigating the shooting and said a knife has been seized.
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