South Korea has vowed to tighten regulations on vaping products and speed up an investigation into whether to ban sales.
"The current situation is considered as a serious risk to public health," South Korea's health minister Park Neung-hoo told a press briefing, citing the pneumonia case of a 30-year-old South Korean e-cigarette user earlier this month.
"Children, juveniles, pregnant women, and people with pulmonary diseases, never use liquid e-cigarettes. Non-smokers, too, never use liquid e-cigarettes from now," the minister added.
Many countries have pulled electronic cigarette products from the market following the 33 deaths and 1,479 confirmed and probable cases from a mysterious respiratory illness tied to vaping in the US.

Six killed in India's Mumbai as rains wreak havoc, disrupt travel
Russian attack on Kyiv kills seven, hits apartments, other buildings
Folarin Balogun to play for US after FIFA suspends red-card ban
Arab League condemns Israeli demolition of entire neighborhood in Lebanon
Venezuela quake death toll nears 3,000 as rescue effort winds down
Eight injured in New York shooting
Trump appears on National Mall for July 4 speech after storm-related delay
Qatar says all maritime activities will resume immediately
