South Korea's former president Yoon handed 30-year term over secret drone flights into North Korea

South Korea's disgraced former president Yoon Suk Yeol has been sentenced to 30 years in prison after a court ruled that he was involved in a covert operation to send military drones over the North Korean capital, Pyongyang. The verdict marks another extraordinary chapter in the downfall of a leader whose presidency ended in turmoil.

The Seoul Central District Court found Yoon and his former defence minister, Kim Yong-hyun, guilty of abuse of power and of aiding an adversary. Prosecutors argued the drone flights, which took place in October 2024, were intended to provoke a hostile response from the North and manufacture the conditions for Yoon's later, short-lived declaration of martial law.

The case has gripped South Korea, a country with a long and painful history of military rule, and has been watched closely across the region given the perennial tensions on the Korean peninsula. The sentence is among the most severe handed to a former South Korean leader in the democratic era.

A pretext for martial law

The court heard that the drones dropped propaganda leaflets over Pyongyang, helping to drive a sharp rise in cross-border tensions. Prosecutors contended that this escalation was not incidental but deliberate, designed to create a sense of national emergency that could justify extraordinary measures at home.

The verdict adds to a life sentence already handed to Yoon earlier in the year for his role in the attempted power grab that triggered his removal from office. That earlier case centred on the night he declared martial law, a move that stunned the nation and was swiftly overturned by lawmakers who defied a military cordon to vote it down.

“He neither ordered nor later approved the drone operation.”

— Lawyers for Yoon Suk Yeol

Yoon, who remains in custody, has denied any wrongdoing throughout the proceedings and is expected to appeal. His lawyers characterised the flights as a response to North Korean balloon launches across the border rather than a deliberate provocation, framing the operation as a legitimate defensive measure rather than a scheme to engineer a crisis.

How the crisis unfolded

Yoon's declaration of martial law was one of the most dramatic episodes in modern South Korean politics. Within hours, troops were deployed and the country appeared to teeter on the brink of a constitutional rupture, evoking memories of the authoritarian governments that ruled before democratisation in the late 1980s.

Lawmakers from across the political spectrum rushed to the National Assembly, some scaling fences to get inside, and voted overwhelmingly to lift the decree. The episode triggered Yoon's impeachment and removal, and set in motion a series of criminal investigations into the events surrounding the declaration, of which the drone case is the latest to conclude.

• Yoon sentenced to 30 years over the drone operation
• Former defence minister Kim Yong-hyun also convicted
• Drones said to have dropped leaflets over Pyongyang in October 2024
• Verdict adds to a life sentence imposed earlier in the year
• Yoon remains in custody and is expected to appeal

Background: a divided peninsula

The two Koreas remain technically at war, the 1950 to 1953 conflict having ended in an armistice rather than a peace treaty. Cross-border provocations, from leaflet campaigns to military exercises, have long been a feature of the relationship, and tensions can escalate rapidly with little warning.

Against that backdrop, the allegation that a sitting president deliberately stoked confrontation with the North for domestic political ends is especially grave. It touches not only on the abuse of power but on the security of a peninsula where miscalculation can carry enormous risks, which helps explain the severity with which the court treated the case.

What happens next

Yoon's legal team has signalled it will appeal, meaning the case is likely to wind through higher courts in the months ahead. South Korea's justice system has, in the past, seen sentences against former leaders modified or commuted on appeal or through later pardons, so the final outcome remains uncertain. Several of Yoon's predecessors were convicted of serious crimes after leaving office, only to be pardoned years later in the name of national unity, a precedent his supporters may yet invoke.

Beyond the courtroom, the saga has left a deep mark on South Korean politics and on public confidence in the country's institutions. The convictions are likely to fuel continued debate about civilian control of the military and the safeguards needed to prevent any future leader from attempting to seize extraordinary powers. They also serve as a stark warning to the wider region that even a mature democracy can be tested when those at the top are willing to bend the machinery of the state to their own ends, and that the strength of a nation's institutions is measured by how it responds.