Methamphetamine lab seizures are on the rise in U.S. cities and suburbs, raising new concerns about a lethal drug that has long been the scourge of rural America.

Data and interviews from an investigation by The Associated Press found growing numbers of meth lab seizures in cities such as St. Louis, Kansas City, Missouri, Nashville, Tennessee, and Evansville, Indiana. Authorities are also seeing evidence that inner-city gangs are becoming involved in meth production and distribution.

"No question about it _ there are more labs in the urban areas," said Tom Farmer, coordinator of the Tennessee Methamphetamine and Pharmaceutical Task Force. "I'm seeing car fires from meth in urban areas now, more people getting burned."

The increase in labs is especially troubling because meth brought into the U.S. from Mexico also is becoming more pervasive in urban areas. The Associated Press reported in October that so-called Mexican "super labs" are upping production, making meth more pure and less expensive, and then using existing drug pipelines in big cities.

Authorities cite numerous reasons for meth moving into cities, but chief among them is the rise in so-called "one-pot" or "shake-and-bake" meth.

In years past, meth was cooked in a makeshift lab. The strong ammonia-like smell carried over a wide area, so to avoid detection, meth had to be made in backwoods locations.

As laws limited the availability of pseudoephedrine, meth-makers adjusted with a faster process that creates smaller batches simply by combining ingredients _ mixing cold pills with toxic substances such as battery acid or drain cleaner _ in 2-liter soda bottles. Shake-and-bake meth can be made quickly with little odor in a home, apartment, hotel, even a car.

"Bad guys have figured it out," said Rusty Payne of the federal Drug Enforcement Agency. "You don't have to be as clandestine _ you don't have to be in rural country to lay low."

Niki Crawford, who heads the meth suppression team in Indiana, said that with shake-and-bake labs, "the odors are not as strong. And they're just so portable. We find them in backpacks and gym bags."

And inside stores: A woman was arrested inside a St. Louis County Wal-Mart earlier this year with a meth-filled soda bottle in her coat pocket.

Another reason for the rise in urban meth is a process known among law enforcement as "smurfing" _the abundance of pharmacies in cities attracts meth-makers from surrounding rural areas, who can bring in friends to help purchase pseudoephedrine pills.

"We know the fuel for domestic labs is pseudoephedrine," Farmer said. "The source for that is pharmacies and the majority of pharmacies are in urban areas."

Farmer also has seen an increase in meth activity involving inner-city Tennessee gangs, which tend to be better-organized than rural cookers when it comes to marketing and selling the drug. For the most part, the gang members work as smurfers, though Farmer worries they'll eventually become involved in the manufacture and distribution of the drug. Sometimes, gang members and meth-makers first connect while in prison.

"They see there's a market there to make money off of pseudoephedrine," Farmer said. "Pseudoephedrine has become as good as currency."