President Yoon Suk Yeol Yoon imposed martial law in the middle of the night earlier this month, plunging South Korea into its worst political crisis in decades.

Suspended president Yoon Suk-yeol authorised the military to fire their weapons if needed to enter parliament, according to prosecutors.

The lawyers for a former South Korean defence minister under investigation on insurrection charges said on Thursday a short-lived martial law decree imposed earlier this month was to raise alarm on opposition parties' abuse of the democratic process.