South Korean prosecutors will pursue President Yoon Suk Yeol's conviction for insurrection despite a court decision ordering the release of the impeached leader from prison, the head of the prosecutors' office said on Monday.

South Korean President Yoon Suk Yeol, who lawmakers voted to impeach, was released from detention Saturday after spending nearly two months in custody under a criminal probe for his martial law declaration.

TV footage showed Mr Yoon coming out of a prison in Seoul, waving his hand and bowing to his supporters. The president declared martial law in December, throwing South Korea into turmoil. He banned political activity and sent armed soldiers inside the parliament, which nonetheless reversed his decision within six hours.