Kim Keon-hee, the wife of former South Korean president Yun Suk-yeol, has been arrested for alleged stock market fraud and irregularities.

She was interrogated for four hours in Seoul but denied any wrongdoing. The court issued an arrest warrant over concerns she might tamper with evidence.

This is the first time both a former president and first lady have been jailed in South Korea. Yun Suk-yeol was arrested earlier this year in relation to Martial Law, which caused political instability.

Kim is accused of illegally earning about $600,000 by rigging stocks of Dutesi Motors, a BMW dealer once managed by her husband.

She also allegedly took expensive gifts during a meeting with the Unification Church and interfered in parliamentary candidate selections.