The mayor of Canada's capital Ottawa has declared a state of emergency in response to more than a week of truckers' protests against Covid restrictions.
Jim Watson said the city was "completely out of control", with demonstrators outnumbering police.
He said the protests posed a threat to the safety and security of residents.
The truckers have paralysed the centre of Ottawa with vehicles and tents blocking roads.
The "Freedom Convoy" began as a movement against a government requirement that the truckers be vaccinated against Covid.
Speaking to Canadian radio station CFRA, Mr Watson said the protesters were behaving increasingly "insensitively" by continuously "blaring horns and sirens, [setting off] fireworks and turning it into a party".
"Clearly, we are outnumbered and we are losing this battle," he said, adding: "This has to be reversed - we have to get our city back."
The mayor did not give specific details about what measures he might impose, but police said on Sunday that they would step up enforcement, including possible arrests of those seeking to aid the protesters.
A state of emergency will give the city additional powers, including access to equipment required by frontline workers and emergency services.
A statement from the city authorities said the state of emergency "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".
Many Ottawa residents have objected to the demonstrations.
Complaints range from idling trucks that impede traffic and makeshift wooden structures in city parks to lost income and fears of harassment and even violence.
Police have said they are concerned about how the convoy has attracted far-right and extremist elements.
They said on Sunday that they were dealing with more than 60 criminal investigations relating to the demonstration, with alleged offences including "mischief, thefts, hate crimes and property damage".
Several people have been arrested and a number of vehicles have been seized, they added.
One demonstrator who drove for hours to join the protest in Ottawa, Kimberly Ball, told AFP news agency that the protest was "about our freedom".
"A couple of people we know, friends, lost their jobs because of these mandates," she said, adding that she had concerns about the safety and effectiveness of Covid vaccines.
Covid-19 vaccines have cut the risk of severe illness in those infected with the virus and serious side effects are extremely rare. Canadians are broadly supportive of vaccine mandates - nearly 83% of the eligible population is fully vaccinated.