The tame, 100-person tent city pitched by G20 protesters in downtown Toronto's Allan Gardens was jolted awake when nearly 500 marchers unexpectedly arrived to join them, led by celebrity author and activist Naomi Klein.
Ms. Klein and a cast of other high-profile speakers held a panel discussion earlier in the evening at Massey Hall, several blocks away.
She concluded her speech by asking the audience to walk to Allan Gardens.
Ms. Klein said the police "didn't expect a bunch of middle-class people who paid $20" for a ticket to the event to start a march in the middle of the night.
As the crowd cheered, organizers asked the audience to continue down to a temporary detention centre on Eastern Ave., where they said a deaf man was being held who had been arrested at a protest earlier in the day. They said he still hadn't been read his rights because a suitable translator could not be found.
Jaggi Singh, another famous Canadian activist, also spoke about the earlier protest. The mainly peaceful protest was marked with several confrontations between heavily armored police and the more than 2,000 demonstrators, including arrests.
Before the unexpected addition to the crowd from Massey Hall, the mood was a mixture of fraught and festive.
Organizers took the microphone to explain the political history of Allan Gardens, one of Toronto's oldest parks.
But before they did there was one other announcement: baby-oil wrestling match in 20 minutes.
There were medics and safety patrols at hand. A thin crowd of bicycle police monitored the sidewalks.
Organizers said there would be free breakfast at 9 a.m., before Saturday's much larger demonstrations begin in earnest, as the first official day of the long-anticipated G20 summit arrives.
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