TORONTO - Chemical and biological weapons units, bomb-sniffing dogs, police on bicycles, horseback and in riot gear will be at the ready in Toronto during the G20 summits.

And those will just be the officers you can see.

Snipers, negotiators and police in the marine unit can also be deployed should protests turn into riots and get out of hand.

The Integrated Security Unit gave a public demonstration Thursday of the massive security operation in place for the summit set for June 25-26. A parallel security plan is expected for the G8 summit in Huntsville on June 24-25.

If all is peaceful people will see police officers patrolling the fenced area around the Metro Toronto Convention Centre — where the summit will be held — just "walking, talking with people," said Toronto police Const. Wendy Drummond.

"What you saw here today is when the public order unit has to come in to protect public safety, property and police officers," she said.

Should they deem it necessary police on bicycles can form one line, with police in riot gear in a line behind and police on horseback behind them. The formation was shown at the demonstration Thursday and the police in riot gear slip quickly in front of the bicycle unit.

"Some Integrated Security Unit members will be seen on the streets of Toronto," said Drummond.

"Others will be harder to spot. Some will be looking from above and some will be on the waterways."

Dozens of extra closed-circuit cameras have been placed throughout the downtown core.

The Emergency Task Force, which serves as support to front-line police, will also be at the ready, consisting of trained negotiators, weapons specialists, snipers, rappel masters and those trained in explosive forced entry, Drummond said.

There is also the explosive device unit, created shortly after Sept. 11, 2001, in which all officers are trained to deal with situations involving chemical, biological, radiological and nuclear weapons.

Their equipment was on display at the demonstration. Provincial Const. Marty Groleau pointed out tools and machines for detecting chemicals or "volatile organic compounds" such as anthrax, ricin, botulism and orthopox, as well as radiation and explosives.

Police also gave a demonstration of their controversial sound devices at 70 decibels, half their capacity, and the so-called sonic cannons could barely be heard over a crowd of dozens of journalists.

The devices, if needed, would only be used for between two and five seconds, Drummond said.

"Any interaction police have with demonstrators will be measured," she said.

"All security planning is done to ensure the safety and security of internationally protected persons, summit staff and dignitaries and the people who work (in), live (in) and visit Toronto."

The four sound cannons purchased by the Toronto police, to be used by the public safety unit, the Emergency Task Force and the Marine Unit, have caused concern among protesters who worry about hearing damage.

"Please be clear in understanding this is not a weapon," Drummond said.

"It is a communications tool that will be deployed to communicate clear and concise information and direction to a large group of people."

Canine units are also responsible for summit security, with dogs that can detect drugs, guns, explosives and people or bodies in search and rescue situations.

Members of the military will be conducting foot patrols around Pearson International Airport, where the world leaders are expected to land.

Canadian Forces are also going to focus on surveillance and observation, "providing early warning to law enforcement agencies on anything that might impact the summit," Drummond said.

Certain services, such as screening access to venues inside the perimeter, have been contracted out to a private security firm. About 1,000 people will be working for that firm under the ISU's mandate, said RCMP Sgt. Leo Monbourquette.

The Toronto police's Marine Unit will be patrolling Lake Ontario, particularly around the Westin Harbour Castle hotel, where many dignitaries are staying. Unlike in Huntsville, where activity on two lakes will be banned during the G8, the water at the base of Toronto will be open.

"Our mandate is to try and be as (minimally) intrusive to the boating public as possible," said Const. Gary Gibson.

There could be temporary restrictions around the Toronto City Centre Airport if dignitaries fly in there, he said.

Motorcades, led by police on motorcycles who will clear traffic ahead, will transport dignitaries from the airport to the convention centre and are expected to cause traffic tie-ups, but only for 15 minutes at a time, police said.

"Make no mistake, traffic congestion will be an issue during the G20," Drummond said.

Police are recommending that people avoid "unnecessary travel" around the affected areas during the G20.

The Integrated Security Unit is comprised of RCMP, Ontario Provincial Police, Toronto police, Peel region police and the Canadian Armed Forces.

"Because we're securing two summits at the same time it is one of the largest undertakings in Canadian history as far as security is concerned," he said.