– The Food and Drug Administration (FDA) on Wednesday declared that teenage use of electronic cigarettes has reached "an epidemic proportion," and it put makers of the most popular devices on notice that they have just 60 days to prove they can keep their devices away from minors.

The order was part of a sweeping government action that targeted both makers and sellers of e-cigarettes. If Juul Labs and four other major manufacturers fail to halt sales to minors, the agency said, it could remove their flavored products from the market. It also raised the possibility of civil or criminal charges if companies are allowing bulk sales through their websites.

The agency said it was sending warning letters to 1,100 retailers — including 7-Eleven stores, Walgreens, Circle K convenience shops and Shell gas stations — and issued another 131 fines, ranging from $279 to $11,182, for selling e-cigarettes to minors.

Federal law prohibits selling e-cigarettes to anyone under 18. In a briefing with reporters, the FDA commissioner, Dr. Scott Gottlieb, said that more than 2 million middle and high school students were regular users of e-cigarettes last year.

The government's tactics underscore a dilemma in the public health community: In addressing one public health problem — cigarette smoking, which kills 480,000 people in the United States each year — e-cigarettes are creating another — hooking teenagers who have never smoked on nicotine.

E-cigarette users inhale far fewer toxic chemicals than do smokers of traditional cigarettes. But they can take in higher levels of nicotine, which is addictive.

"The developing adolescent brain is particularly vulnerable to addiction," the FDA said in its statement announcing the actions.

In particular, the agency has been watching the wildly popular Juul, which offers especially potent nicotine hits. Juul Labs launched the sleek device, which looks like a flash drive, in 2015. In a short time, Juul has become the dominant seller of e-cigarettes and a fad among students. According to Nielsen data, Juul controls 72 percent of the market, and is valued by investors at $16 billion.

In an e-mailed statement, a Juul spokeswoman said: "Juul Labs will work proactively with FDA in response to its request."

Gottlieb said the FDA would look closely at whether Juul and other manufacturers were allowing bulk purchases of products through their own websites — a practice where the buyer could then sell to minors. If such "straw sales" are happening, it should be readily apparent to the manufacturers, he said.

The other four products facing the 60-day deadline are RJR Vapor Co.'s Vuse, Imperial Grand's blu and devices made by Logic. They said they were working with the FDA as well.

Gottlieb's aggressive approach against private industry is unusual for an official in the business-friendly Trump administration that has sought to roll back numerous environmental and health regulations. But critics said that his decision last summer to extend a deadline for e-cigarette manufacturers to demonstrate that their products comply with public health concerns helped perpetuate the current problem.

"It's nice they want to do something but realistically, what are they going to accomplish this way when they could be so much more effective by following the regulatory plan that had been ready to put into place and that the commissioner postponed?" said Diana Zuckerman, president of the National Center for Health Research, a nonprofit health policy group.

The attorney general of Massachusetts, Maura Healey, who recently began an investigation into the marketing and sale of e-cigarettes to minors, praised the FDA's action.

"We've worked too hard over the past 50 years to reduce smoking rates among young people to let these companies profit off of getting them hooked on nicotine," Healey said. "This move by the FDA is a good first step to shut down companies targeting minors."