Police demonstrate G20 security and crowd control measures in Toronto on Thursday. (Frank Gunn/Canadian Press)

The police and military who will provide security at the G20 Summit in Toronto later this month gave a demonstration on Thursday of some of the tools at their disposal to protect the city and citizens.

The security plan for the G20 in Toronto and the G8, which will be held in Ontario's cottage country, near Huntsville, has an estimated cost of more than $1 billion.

It will be the biggest security operation ever in Canada, according to police.

On Thursday security forces used a police training facility in Toronto's west end to give the media a first-hand look at how some of that $1 billion will be spent.

Police from the Toronto area and across the country, as well as the Armed Forces, are part of the operation.

There will be numerous motorcades for the dignitaries, said police, which will mean lots of traffic police, escort motorcycles and police sirens.

The security operation will also involve crowd control. One of the most controversial aspects is the decision by police to buy four long range acoustic devices, known to police by the acronym LRAD, but more commonly referred to as sound cannons.

"Basically it's a warning [device]," said Toronto police Staff Insp. Bill Neadles.

"I think people believe we're going to use that sound notifier as a weapon. We have no intention of doing that," he said.

Police intend to deploy the devices around the city — three on the ground and one in the harbour.

Members of the Canadian military will take up security posts at Pearson International Airport.

Lt.-Col. Liam McGarry, who is in charge of ground forces in Toronto, said the soldiers don't intend to put on a display, but the public should know the soldiers will be fully equipped.

"They will be carrying the weapon … the C7A1 rifle," said McGarry.

The final tab for the three days of meetings is expected to cost $1.2 billion.

Federal ministers argue that the costs are necessary to ensure the summits are secure, pointing out this is the first time a country has been host to two summits back to back.

The Opposition Liberals say the costs are exorbitant and an example of incompetence and mismanagement.

The G8 summit runs June 25-26 in Huntsville and the G20 in Toronto runs June 26-27.