A team of Toronto police investigators is spending 12-hour days behind computer and video monitors, looking for tiny clues in images to identify those responsible for a massive vandalism spree at the G20 summit this past June.

They are sorting through more than 40,000 still images and countless hours of videos, taken during the June 26-27 meeting of world leaders in Toronto.

Their foes used so-called Black Bloc tactics.

The vandals joined a massive, peaceful labour-sponsored march on June 26. They emerged out of the crowd on Queen Street, dressed in black, and went on a 90-minute rampage in the downtown core outside the inner and outer G20 security zones.

Business windows were smashed and six police cruisers either torched or otherwise damaged.

As the vandalism wound down, the vandals -- who numbered in the hundreds -- went to great lengths to hide their identities as they stripped off their black clothing and blended back into the crowds.

Police had aircraft and satellite images to supplement the CCTV cameras mounted on streetlight posts, images captured by undercover officers and those sent in by the public.

But the vandals knew they were being watched from above.

They would form a circle and hold up an umbrella. After their fellow vandals stripped off their black clothing, they would look like almost anyone else on the street.

"If you watch the tactics, they'll all face out," Det. Mike Jander told CTV Toronto. "They'll all face out with the umbrellas out to block it."

CTV Toronto cameras captured some of the vandals "de-bloc-ing" on that chaotic day, even though their fellow vandals tried to shield them.

But while people can shed their clothes, they can't easily shed other physical aspects of their identity, such as:

  • piercings
  • tattoos
  • sunglasses
  • shoes

Jander and Det. Bill McGarry are part of the squad that operates out of a secret location.

"As you get closer to their body, they have has something that makes them uniquely different from the next Black Bloc person," McGarry said.

With one person of interest, it's what's on their head.

"This is a male that looks like him. He's got the same hat," McGarry said. "I'd have to see what else he was wearing and compare his clothing.

Looking even closer at the images of another suspect, they can find even more unique identifying marks.

"He has what appears to be a mole or a mark on his arm," McGarry said. "It's kind of hard to seen on the screen but he actually appears to have the same thing."

A search of the Internet revealed the man to be playing drums in a band.

They think he lives in New York state, and are working with police there to identify and possibly arrest the man. Det. Sgt. Gary Giroux, who heads the G20 team, has said at least two of his "worst of the worst" suspects are from the New York City area.

Every person of interest has a file folder into which their photos are dropped.

Police have periodically released photos of G20 suspects, seeking the public's help in identifying suspects. They last sent out an update on Wednesday.

The last new suspect arrest was announced on Sept. 10. More than 20 arrests have been made by the team to date.

Giroux has said he believes the team has rounded up most of the GTA and southern Ontario-based suspects.

While more than 1,100 people were arrested on that weekend, about three-quarters were never criminally charged. Almost 60 others had their charges dropped last month.

More than 230 cases remain before the courts, including those of 17 people the police consider ringleaders.

But the number doesn't include those as yet-unidentified suspects the G20 detectives are still seeking.

With a report from CTV Toronto's Austin Delaney