South Korea said on Saturday that the number of new coronavirus cases in the country had doubled to 433, and officials suggested the tally could rise significantly as more than 1,000 people who attended a church at the center of the outbreak reported flu-like symptoms.

Korea's Centers for Disease Control and Prevention reported 142 new cases at a morning briefing and another 87 in the afternoon.

Of the new cases, most have been linked to outbreaks at a branch of the Shincheonji Church of Jesus in Daegu and a hospital in Cheongdo county. Also among the new cases were the first reported infections in Busan, South Korea's second-largest city, and on Jeju, a resort island that's a popular tourist draw.