Juul warned over claims its e-cigarette safer than smoking

Federal health authorities have blasted vaping giant Juul for illegally pitching its electronic cigarettes as a safer alternative to smoking and ordered the company to stop making unproven claims for its products.

The Food and Drug Administration also upped its scrutiny of a number of key aspects of Juul's business, telling the company to turn over documents on its marketing, educational programs and nicotine formula.

The FDA action increases the legal pressure on the nation's best-selling vaping company, which has been besieged by scrutiny from state and federal officials since a recent surge in underage vaping. Federal law bans sales to those under 18. The FDA has been investigating Juul for months but hadn’t previously taken action against the company.

A Juul spokesman said the company is reviewing the FDA comments and "will fully cooperate."