Canada-based gangs are taking control of the production and distribution of the drug ecstasy in the United States, according to a U.S. government report.

"Since 2004 Canada-based Asian criminal groups — primarily ethnic Vietnamese and Chinese — have been expanding MDMA [ecstasy] distribution and have significantly elevated MDMA availability," according to the annual drug threat assessment by the U.S. National Drug Intelligence Center.

It said an estimated $5.2 billion to $21.2 billion US is generated by Canada-based drug trade organizations through the distribution of marijuana and ecstasy, also known as methylenedioxymethamphetamine or MDMA.

Despite the billions of dollars spent on antidrug efforts, the report said illegal drugs, from marijuana to heroin, are easily accessible across the United States.

RCMP Supt. Paul Nadeau, director of the agency's drug branch in Ottawa, said it's no big surprise that some of the drugs come from Canada.

Nadeau said he agrees with parts of the U.S. report that reveal changes in Americans' appetite for drugs and how Canadian-based gangs are responding.