South Korea's latest COVID-19 outbreak has triggered a public backlash against conservative Christian churches for defying government orders aimed at preventing the disease's spread.

At least a third of the 4,500 COVID-19 cases confirmed in the greater Seoul area over the past three weeks have been traced to church members and others who attended an Aug. 15 anti-government rally, the country's largest cluster in months.

Authorities said quelling the outbreak was hampered by some 650 church members and 7,700 protesters avoiding or refusing testing as of Tuesday, and more than 300 congregations breaching a ban on in-person gatherings.