United States government health officials are moving forward with a plan designed to keep electronic cigarettes out of the hands of young people. The plan would restrict sales of most flavored e-cigarettes at drug stores, gasoline stations and other businesses that sell them. The U.S. Food and Drug Administration, or FDA, first proposed the new rules last November. They are the latest government effort to fight what health officials call an epidemic of young people using the devices. E-cigarettes usually heat a flavored substance made with nicotine, a highly addictive chemical. The solution becomes a vapor, a gas that can be breathed in much like cigarette smoke. U.S. federal law bans the sale of e-cigarettes to anyone under 18 years of age. But a study published last year found that 1 in 5 high school students report using the devices: an activity known as vaping. Last week, the FDA announced that e-cigarette makers would need to restrict sales of most flavored products.