This photo shows the police's National Office of Investigation in Seoul, Dec. 9. Yonhap

Police said Wednesday they were questioning the commander of a military armored unit on suspicion of participating in preparations for the brief imposition of martial law this month.

Police summoned Brig. Gen. Koo Sam-hoe, commander of the 2nd Armored Brigade, over his alleged attendance of a meeting of former and incumbent military and defense officials at a fast food restaurant in Ansan, southwest of Seoul, on Dec. 3 — the day of the martial law declaration.

Koo has been accused of attempting to mobilize a tank unit during martial law.

At the restaurant, Koo allegedly plotted preparations for martial law with Noh Sang-won, a former commander of the Defense Intelligence Command, whom police arrested last week. (Yonhap)