TORONTO - A city already on edge ahead of the G20 summit was given another jolt Thursday when police pulled over a suspicious car downtown and discovered a surprising cargo that included a crossbow.

The 53-year-old driver was immediately arrested, the area sealed off as officers wearing hazardous material "moon suits" checked suspicious liquid in the vehicle.

Toronto police say Whitby resident Gary McCullough has been charged with one count of dangerous weapons.

"We have a crossbow, there's a chainsaw, baseball bat, sledge hammers," said Const. Hugh Smith.

"There's quite a various amount of items that, used by the wrong person at the wrong time, was enough that we made the arrest."

Police were keeping a close eye on a noisy but otherwise peaceful labour demonstration outside a hotel when the man drove by at the lunch hour in his modified silver Hyundai Elantra.

The car immediately drew suspicion, and officers pulled it over.

"Some of the weaponry was openly exposed," Smith said.

Police later said none of the items were illegal to have.

Also found were several jerry cans containing an unknown liquid.

Police cordoned off the area with yellow tape, and part of the scene with red tape as fully equipped hazardous-materials experts in green and red boots and carrying oxygen tanks checked the liquid taken from the vehicle.

They later concluded the liquid was nothing out of the ordinary.

Police said the man was taken to a processing centre and charges would be pending, but said it appeared the incident was not related to the G20 summit that runs this weekend.

"There's no evidence to indicate or suggest that it's G20-related," said police spokesman Tony Vella.

"The area is rendered safe -- it's controlled now."

As officers investigated the latest scare, two blue containers and at least three red gas cans could be seen on the road while the stash of other items were stacked on the sidewalk.

The car, which had a large storage box strapped to the roof and also contained a pickaxe, caught the attention of officers because it didn't appear to be roadworthy, police said.

Much of downtown Toronto is behind police fences and barricades for the G20 summit, and police have been out in force patrolling the city.

The incident occurred a few blocks east of the main security zone.

The arrest came as about 80 workers picketed the Novotel Toronto Centre after walking off the job early Thursday.