Canada on Thursday unveiled the arsenal it will use against protesters who get out of hand at two global summits later this month, promising riot police armed
with guns, shields, Tasers and super-high-volume loudspeakers.

Toronto police said their new Long Range Acoustic Device would help them communicate with roaring protesters from as far as 250 meters (820 feet) away. When turned to full volume,
the devices can emit enough sound to damage eardrums.

"This is not a weapon," said Constable Wendy Drummond, a spokeswoman for the Integrated Security Unit that will provide security for the two
summits. "It is a communications tool. It may or may not even be used."

Security forces have bought four of the portable loudspeakers, also known as a sonic guns because the volume can be turned up to such levels they can
be used as weapons.

The devices look harmless enough, like a large, home stereo speaker that can be strapped to an officer's chest. Protest groups say they should not be
allowed because the sound can be turned to as loud as 146 decibels, or
the equivalent of a firecracker exploding by your ear.

Canada faces a billion-dollar bill for security at the summit of the Group of Eight industrialized countries and the summit of the Group of 20 rich
and developing nations. The events take place at the end of the month
in Toronto and in Huntsville, Ontario, a resort town two hours to the
north.

The agendas will focus on the financial crises that has torn across the globe. As in past summits, the meetings are becoming magnets for environmental and
anti-poverty campaigners who see it as a perfect forum for protest.

"We have had a large number of them (protesters) that have communicated with us and talked to us about what their plans are," Drummond said
after a police demonstration of ways they plan to keep the peace at the
Toronto summit.

"We have some that have chosen not to speak with us and work with us. I can't speak to any numbers, all I can say is that we are going to be prepared for any
eventuality."

A riot would be met with police squads on foot, on mountain bikes and on horseback, officials said.

In their demonstration, police resembled Roman centurions as they showed how teams would work together from behind transparent shields to repel
protesters.

Police in cruisers and motorcycles will escort motorcades to and from the conference, which will take place behind 3-meter (10-foot) high steel fences.

The financial core in Toronto, Canada's largest city, will also lie within the cordoned off area, while an outer security zone will also be closed
to protest groups.

Cameras will monitor public places and the images could later be used as court evidence of criminal acts.

"This is Canada's largest security event and I think people can appreciate how much resources are being put into these summits to protect
dignitaries as well as the community of Toronto," said Drummond.

Security is not the only issue on the agenda for Toronto. Workers at some two dozen Toronto hotels gave their union a strike authorization vote on
Thursday, although CTV television said only one downtown hotel would be
affected by any walkout.