TORONTO - Two local street gangs that apparently operated violently in obscurity were rounded up in a nation-wide sweep netting 60 people.

The Young Buck Killas and the G Siders were nabbed when more than 900 police officers executed 67 search warrants simultaneously in Toronto, Windsor, Hamilton, London and Ottawa in Ontario; Saskatoon; Calgary, Edmonton, Fort McMurray, Alta., and Surry and Vancouver, B.C.

The raids were part of the Toronto-based Project Marvel, which involved criminal organization offences, attempted murder, firearms trafficking and importation, drug trafficking, robbery, shootings, prostitution and other criminal offences, police said.

Toronto Police Chief Bill Blair said the probe was launched in May following a violent street robbery and shooting.

But the scope of the project wasn't realized until police in London, Ont. -- already targeting some of the same people -- arrested a number of people tied to the YBK during a car stop in connection with the robbery, Blair said.

Now, the accused, including 10 youths, are facing charges in connection with attempt murders, drugs, weapons trafficking, prostitution and pimping, and possibly murder.

A number of unsolved Toronto murders are also being reviewed after about 20 firearms were seized by raiding officers, including a military-style rifle, Blair said.

Police also seized cash and drugs, mostly cocaine.

Blair said the two gangs were from different neighbourhoods but "not necessarily rivals."

"The project quickly developed into (a probe into) criminal organizations, involving two criminal gangs," Toronto organized crime unit Supt. Chris White said.

Blair said what was unique to this project was the mobility of gangs.

"This became a national investigation," he said.

"This started off as an isolated project," he said. "It quickly became evident it was much more organized and it branched out from there."

A few of those arrested appeared in court on Tuesday.

One mother said she was at court to bail out her 14-year-old son, who was arrested early Tuesday.

The mom alleged cops came bursting through her apartment and the noise was so loud that she thought "it was gunmen."

"They broke down my door," she said. "My apartment is freezing cold."

Police in Hamilton raided two homes.

In London, officers conducted two pre-dawn raids.

Windsor police raided three homes.

Officers in Windsor arrested one suspect.

In Calgary, officers took one man into custody, though he has not yet been charged. No one was arrested in Edmonton or Fort McMurray.

Officers in Gatineau, Que., also arrested a suspect.

— with files from Bill Kaufmann and Doug Hempstead, Tom Godfrey