South Korea’s special prosecutor has indicted former President Yoon Suk Yeol on additional charges of abusing power and aiding an enemy state over his short-lived martial law declaration last year.

Prosecutors allege Yoon, along with former defense minister Kim Yong-hyun and ex-military intelligence chief Yeo In-hyung, planned to provoke North Korea—potentially using drones or “surgical strikes”—to justify imposing martial law.

Yoon, removed from office by the Constitutional Court in April, faces trial for insurrection and could face the death penalty if convicted.

The special prosecutor claims the trio conspired to inflame tensions and that South Korean drones may have been sent into the North to support their plan, CNN has reported.

Yoon denies intending military rule, saying martial law was meant to expose opposition wrongdoing and protect democracy, while Yeo has expressed regret for not challenging Yoon’s orders.