Police in riot gear and protesters continued to clash Saturday evening following a massive anti-G20 protest march through downtown Toronto that saw at least two police vehicles set ablaze, store and bank windows smashed, and much of the area put under security lockdowns.

The police cruisers were torched at the corner of King and Bay streets in the heart of the city's financial district, sending plumes of black smoke into the air. At one point, as one vehicle burned, protesters surrounded police officers who were trying to protect the car, CBC reporter Amber Hildebrandt reported on Twitter.

The size of the protest crowd was estimated to be as high as 10,000. Witnesses said tear gas had been used in the area around the provincial legislature at College and University, but police denied any had been used in the city.

Toronto Mayor David Miller said a small group of "thugs" are to blame for the violence.

“People are calling them protesters. That is not fair to the people who came to protest,” he said.

Toronto police Sgt. Tim Burrows said there have been minor injuries. He added he couldn't confirm how many people have been arrested.

Semitic illegal drug calls Khat spreads in North

America and Europe

The summit was set to begin later Saturday evening with a working dinner hosted by Prime Minister Stephen Harper.

With the violence escalating in the heart of Canada's largest city, the entire area around the summit site at the Metro Toronto Convention Centre — enclosed by concrete barricades and fences — is under a security lockdown.

Transit halted

The area's boundaries include Wellington Street to the north, Lakeshore and Bremner boulevards to the south, Windsor Street and Blue Jays Way to the west and a section of Bay Street to the east.

Subway service in downtown Toronto remained suspended, with no service in the loop between Bloor and St. George stations, and no streetcars or bus service, as well service in and out of Union Station has also been stopped.

A police car burns after G20 summit protesters set fire to it in downtown Toronto on Saturday. (Chris Young/Canadian Press)

The airspace over downtown Toronto has also been closed, as has the Gardiner Expressway, one of the city's major traffic arteries.

Some hospitals, hotels, businesses and the tourist attraction the Eaton Centre are also under lockdown.

As the demonstration started just after 1 p.m. ET at the Ontario legislature, the mood was upbeat and peaceful. Protesters danced, clapped and chanted while carrying signs, flags and umbrellas as they first moved from the legislature grounds down one of the city's main thoroughfares, University Avenue.

But the mood turned ugly as anarchists in a splinter groups broke away in attempts to move toward the summit site. They dress similar to members of the Black Block, a group that has used violence such as widespread vandalism in past G20 protests.

Group members are known for wearing black hoodies, masks, balaclavas and skateboard helmets.

As the hours went on, protesters smashed windows on both sides of Yonge Street at the normally busy shopping area in the Yonge-Dundas corridor. Witnesses said rioters smashed the info booth of the large Future Shop electronics store.

"It's a sizable crowd and getting bigger and bigger" in some areas, the CBC's Steven D'Souza reported. "It doesn't look too dangerous, but it is gathering momentum where I am right now."

'Why do they come here and make problems and make problems for every store?'— Myung Hwon Yang, store owner."

Steven Connor, who works at the Hard Rock Café near the Eaton Centre, said several glass store fronts were smashed, with some protesters using street pylons and road equipment, as some people were inside.

No one seemed to be injured, Connor said.

"There's been a lot of damage in the downtown core," the CBC's Michael Serapio reported.

Michael Hyatt, who was at a gym near Yonge and Dundas streets, said the protesters seemed to target a number of U.S.-based chains.

“It is pretty horrible what they have done to a lot of the stores here. They’ve destroyed the windows at an American Apparel — they destroyed all the windows and pulled out the mannequins and [threw] feces into the store.

“It stinks and it is unbelievable. Foot Locker is destroyed. Pizza Pizza is destroyed. They’ve kind of gone up the street and picked at every U.S. vendor they could find. It’s really kind of sad.”

Bricks, rocks thrown

On many downtown streets, many store windows were either broken with bricks or rocks, or defaced with graffiti. One bank on Queen Street West had its windows smashed, and a CBC van was damaged.

One convenience store owner said he was determined to stay open.

Protesters, including some who were wearing masks, take part in Saturday's march. (Nazim Walji/CBC)

"It's important for countries to meet, but an island area is better. Why do they come here and make problems and make problems for every store?" Myung Hwon Yang told CBC News.

In one incident, a man dressed in red was arrested and then dragged screaming into a police van. As it happened, a large crowd gathered, denouncing police and chanting "Let him go."

Miller said police took thorough preparations ahead of the summit and did a "commendable job under difficult circumstances."

"I'm sure there have been small moments where perhaps there’s some tensions between a crowd and the police," Miller told reporters. "In the broad brush, I think we should be very confident in their work."

He added that Toronto police Chief Bill Blair had been very clear in recent days that authorities would facilitate a lawful, democratic protest, while expressing concern about groups who "come here just to perpetrate violence."

Surviving the G20 summit

By CBC News
CBC News

The security perimeter stretches past Union Station.

The security perimeter stretches past Union Station. (Ramya Jegatheesan/CBC)

Many Torontonians have fled to greener, fence-free pastures, but if you're stuck in town here's a guide to surviving the summit weekend.

Many Torontonians are fleeing the city to greener, fence-free pastures this weekend, leaving the downtown core looking like a ghost town, but there are a few who must or want to stick around for the G20.

Whether you failed to secure a spot at a friend's cottage or you're a protest tourist or a protester yourself set to hit the pavement, here's a guide for how to survive the summit weekend.

How to dress:

Offices and condominium managers have sent out advice to employees and residents, urging them to dress casual so as not to become a target.

"Business attire," one property management company with two buildings near the perimeter told residents in a four-page guide, "may put you in a susceptible position."

The guide by Enhanced Management Services, which manages of 19 and 23 Brant St. near King Street, advised residents to wear casual clothes. Similar guidelines went out to office workers in the security perimeter area.

As to what casual, non-threatening attire is, that's open to interpretation.

What to stock:

The same condominium manager urged residents to leave town if possible and stock up 72 hours' worth of food and water, suggesting two liters of water per person per day. Other items that may be worth stockpiling for those living or working downtown include:

Manual can opener.
Flashlight and batteries.
Battery-powered or wind-up radio.
First aid kit.
Cash in smaller bills such as $10.
Extra keys for car and house.
Change for pay phones.

In case of injury

Hospitals are on high alert this weekend, with co-ordinated plans for deploying staff if large numbers of people require medical attention. Many hospitals have set up outdoor tents to serve as decontamination stations to treat people affected by noxious substances like pepper spray or tear gas.

"Really what we're preparing for in the most part is just minor things like heat and traffic disruptions," said Dr. Harold Ovens, director of the Schwartz/Reisman Emergency Centre at Mount Sinai Hospital.

If you plan to sightsee at a protest or take part, here are a few tips:

Drink lots of water.
Soak a bandana in lemon juice or vinegar and carry it in a Ziploc bag. Use the cloth to breathe if tear gas is used.
Sunblock, light clothing and close-toed shoes are advisable.
Watch the protesters around you. If it looks like violence could occur, leave immediately.
Watch the police. They're trained in protests. If you see them putting gas masks on, get out your vinegar-soaked kerchief.
Bring ear plugs in case you encounter a sound cannon.

Source: Integrated Security Unit, protest groups

Paramedics will also be on hand at protests to help anyone who gets injured.

Location of protests

Whether you want to join in or keep your distance, the Toronto Community Mobilization Network, an umbrella protest group, has a list of planned protests for both Saturday and Sunday.

The protest areas at Queen's Park North and Allan Gardens will likely be popular, Burrows said, as will the downtown summit perimeter fence.

See the list of events for Saturday [http://g20.torontomobilize.org/event/2010/06/26/day] and Sunday [http://g20.torontomobilize.org/event/2010/06/27/day].

Your rights

News emerged Friday [http://www.cbc.ca/canada/toronto/story/2010/06/25/g20-new-powers.html] that recently implemented legislation has given police new powers for the duration of the G20. Under the regulations, anyone who comes within five metres of the security area is obliged to give police their name and state the purpose of their visit, upon request. If they fail to provide ID or give a reason, they can be searched and arrested.

"Our officers have been advising people of the restrictions from the weekend, just not the wording of the act," Burrows said of the legislation.

"We've seen that his concern was justified," Miller said.

Behind the banners: Protester profiles

Behind the banners
By Amber Hildebrandt and Timothy Neesam

For the week leading up to the G20 Summit, thousands of protesters have descended on the streets of Canada's largest city — many visiting but largely drawn from its own communities.

Daily marches and rallies and mock summits have taken over parks and streets and buildings. Drumming, singing, chanting has supplanted the angry hornet strains of the World Cup vuvuzela.

We've heard about the numbers — 1,000 here, 200 there — and the causes, but what about the the faces in the crowd?

The following is a look at what brought the protesters to the streets this week, what drew them into activism in the first place and what, if they could tell the G20 one thing, their message would be.

Behind the banners: Protester profiles.

To see the photos please click here: http://www.cbc.ca/canada/g20streetlevel/2010/06/behind-the-banners-protester-profiles.html

and

http://ca.news.yahoo.com/nphotos/slideshow/ss/events/wl/100525_g20protests#photoViewer=/26062010/2/photo/national-riot-police-walk-burning-police-car-downtown-toronto-during.html