SEOUL: South Korea reported 686 new coronavirus cases on Wednesday as it battles a third wave of infection that is threatening to overwhelm its medical system.

The daily tally was the second-highest since the start of the pandemic, according to the Korea Disease Control and Prevention Agency (KDCA).

New cases have been consistently around 600 over the past week.

Tougher social distancing rules took effect on Tuesday, including unprecedented curfews on restaurants and most other businesses.

The government has also introduced a new testing method to cater to surging demand, and eased rules to release some recovered patients faster to free up hospital beds.

The government has signed deals with four global drugmakers to procure COVID-19 vaccines for 44 million people.

South Korea's total infections stand at 39,432, with 556 deaths.