Police have summoned former President Yoon Suk Yeol as a suspect over allegations that he ordered the secret service to prevent law enforcement from arresting him over martial law in January.

At a press briefing on Monday, an official at the National Police Agency said investigators summoned Yoon for questioning this coming Thursday after he failed to respond to an initial summons last month to appear on Thursday last week.

This is the first time the police have summoned the impeached president since he briefly imposed martial law on December 3.

Aside from being suspected of special obstruction of public duty regarding the arrest attempt, Yoon is also alleged to have ordered the deletion of data on December 7 related to secure phones used by military commanders involved in martial law.

Based on a nearly completed analysis of a secure phone server submitted by the Presidential Security Service, the official said there was a record of calls Yoon made to the nation’s police chief, Cho Ji-ho, and Seoul’s then-police chief, Kim Bong-sik, right after declaring martial law.