Ottawa Mayor Jim Watson on Sunday declared a state of emergency to help deal with an unprecedented 10-day occupation by protesting truckers that has shut down much of the core of the Canadian capital.
"(This) reflects the serious danger and threat to the safety and security of residents posed by the ongoing demonstrations and highlights the need for support from other jurisdictions and levels of government," he said in a statement.
Watson, who complained earlier in the day that the demonstrators outnumbered police and controlled the situation, did not give details of what measures he might impose.
The "Freedom Convoy" began as a movement against a Canadian vaccine requirement for cross-border truckers but has turned into a rallying point against public health measures and Prime Minister Justin Trudeau's government.
Amid residents' fury at the lack of official response, Ottawa police relocated some protesters and put up fresh barricades on Sunday, saying they are "collecting financial, digital, vehicle registration ... and other evidence that will be used in criminal prosecutions."
They also announced they would clamp down on people attempting to bring in canisters to refuel the hundreds of large trucks blocking most roads in the city center.
Protesters have paralyzed downtown Ottawa for the past nine days, with some participants waving Confederate or Nazi flags and some saying they want to dissolve Canada's government. Convoy organizers say they will not leave until the vaccine mandates are ended.
Canadian Public Safety Minister Marco Mendicino said on Sunday that the government would not back down on the issue.
"We put the question of vaccines and vaccine mandates on the ballot ... in the (2021) election and we're simply carrying out the promise that we made with the support of the vast majority of Canadians," he said on CBC television.
Amid incessant horn blaring and occasional fireworks, a polished supply chain -- including portable saunas, a community kitchen and bouncy castles for children -- has sustained the protesters.
The well-organized blockade has relied partly on funding from sympathizers in the United States, police said. GoFundMe took down the Freedom Convoy's donation page, angering some US Republican lawmakers who pledged to investigate the move by the website.
Former US President Donald Trump and Tesla CEO Elon Musk have praised the truckers.
Police said they had charged four people with hate crimes and were investigating threats against public figures jointly with the US Federal Bureau of Investigation.
Trudeau, who is isolating after testing positive for Covid-19 last week, has ruled out using the military to disband the protest. Due to security concerns, Trudeau and his family left their downtown home last weekend and his location has not been disclosed.
The prime minister has said the convoy represented a "small fringe minority" and the government would not be intimidated. About 90% of Canada's cross-border truckers and almost 79% of the population has had two Covid-19 vaccine shots.
Convoy organizers said they would refrain from using their horns on Sunday for four hours "as a gesture of goodwill".
A senior member of the Liberal government said the ease with which the convoy shut down the area around the parliament and the seeming impotence of police was a "national humiliation".
Senior opposition Conservatives who encouraged the protests, including taking selfies with truckers, did not reply to requests for comment. Last week, the party ditched its leader in part for not initially backing the blockade enthusiastically enough.