Canadian police on Saturday used pepper spray and stun grenades in an attempt to restore normalcy in Ottawa, parts of which have been paralysed by protesters opposing the government's pandemic restrictions.

Here is a timeline of the main events:

Nov 19 - Prime Minister Justin Trudeau's government announces that all cross-border truck drivers will be subject to mandatory vaccine and quarantine requirements from Jan. 15. The trucking industry association has warned the mandates could intensify supply-chain disruptions but opposes protests on public roads.

Jan 28 - A convoy largely consisting of trucks starts arriving in Ottawa from across Canada opposing the vaccine mandate. A similar requirement is in place in the United States.

Jan 29 - Thousands of protesters under the banner "The Freedom Convoy 2022" hold a loud but peaceful protest in downtown Ottawa.

Jan 31 - Trudeau, who was moved to a secret location, says Canadians are disgusted by the behaviour of some protesters in Ottawa and says he will not be intimidated.

Feb 2 - Leader of Canada's main opposition Conservative Party, Erin O'Toole, is ousted after a caucus vote, partly because of his failure to embrace the anti-government protest quickly enough.

Feb 5 - Protesters occupy downtown Ottawa for a second straight weekend. Protests spread to other cities including the financial capital Toronto.

Feb 6 - Ottawa Mayor Jim Watson declares a state of emergency.

Feb 7 - Police seize thousands of litres of fuel and remove an oil tanker supplying the trucks. A court grants an interim injunction preventing people from sounding horns in downtown Ottawa.

Feb 7 - Protesters start blocking the Ambassador Bridge in Windsor, Ontario, the busiest crossing between Canada and the United States, and protesters block other border points in Alberta and Manitoba.

Feb 8 - The blockade disrupts trade between the two countries. Ford Motor Co, General Motors Co and Toyota Motor Corp halt some production.

Feb 10 - The Biden administration urges Canada to use federal powers to ease the disruption at the US-Canada border.

Feb 11 - A Canadian judge orders an end to the blockade of the Ambassador Bridge and the province of Ontario declares a state of emergency. Protesters defy the court order and remain.

Feb 13 - The Ambassador Bridge reopens after a six-day blockade as Canadian police clear protesters.

Feb 15 - Trudeau invokes rarely used special emergency measures to tackle protests.

Feb 16 - Ottawa's police chief resigns.

Feb 17- Police warn protesters occupying central Ottawa of "imminent" action.

Feb 18 - Police begin to push into crowds of demonstrators, arrest more than 100 and haul away vehicles. Key organisers are arrested.

- Reuters