South Korean prosecutors said on Sunday they had sought court approval to detain the head of a military drone unit as part of an investigation into former President Yoon Suk Yeol and drone operations in neighboring North Korea.
Prosecutors stepped up a probe into the drone operation after indicting the jailed ex-President Yoon on Saturday on additional charges for his short-lived declaration of martial law in December.
They had summoned the unit's chief, Kim Yong-dae, on Thursday regarding accusations that Yoon ordered a covert drone operation into the North last year to inflame tension between the neighbors to justify his martial law decree, Reuters reported.
Yoon has denied the accusations.
Kim told reporters the incident was part of a "clandestine military operation" in response to trash balloons sent from the North and not intended to provoke the neighboring nation.
In October, North Korea said the South had sent drones to scatter anti-North Korea leaflets over Pyongyang, and published photos of the remains of a crashed South Korean military drone.
South Korea at the time declined to disclose whether it had sent the drones.
In a statement on Sunday, the prosecution office said it had sought an arrest warrant for Kim. Media said a court hearing is planned for Monday afternoon to review the request for a warrant.
He was arrested on Friday without a court warrant, media said. Prosecutors and police are permitted to make an "emergency arrest" if they have a strong belief someone is guilty of a serious crime and may flee or destroy evidence.
