South Korea's Constitutional Court overturned acting President Han Duck-soo's impeachment, reinstating the nation's No. 2 official as acting leader on Monday.

Tens of thousands from both sides mass on the streets of Seoul in the run-up to the decision on ousting President Yoon.

A South Korean appeals court reversed on Wednesday a lower court's ruling and found main opposition leader Lee Jae-myung not guilty of violating the election law, removing a barrier that could have blocked him from running for president.