WASHINGTON (AP) — E-cigarette giant Juul Labs is facing mounting scrutiny from state law enforcement officials, with the attorneys general in Illinois and the District of Columbia investigating how the company’s blockbuster vaping device became so popular with underage teens, The Associated Press has learned.

Juul CEO Kevin Burns said Thursday that non-smokers should not use his company’s product. “Don’t vape. Don’t use Juul,” Burns said during an appearance on CBS This Morning. “Don’t start using nicotine if you don't have a preexisting relationship with nicotine. Don’t use the product. You’re not our target consumer.”

The CEO of the popular e-cigarette company Juul called the nearly 200 cases of vaping-related illnesses “worrisome” — but said his popular products will stay on the market "until we see some facts.”

Speaking to "CBS This Morning," Kevin Burns addressed the series of vaping-related lung illnesses reported in at least 22 states that have resulted in dozens of hospitalizations and at least one death.

The cases are “worrisome for the category,” Burns told the outlet. “Worrisome for us if we contributed to it.”