An armed man was arrested after staging a hostage situation at the local office of the main opposition party chief Wednesday, police said.

The 55-year-old man, identified only by his surname Chung, stormed into the office of Moon Jae-in of the Minjoo Party of Korea -- formerly the New Politics Alliance for Democracy -- in the country's second-largest city of Busan, with a weapon at around 9:10 a.m.

Moon was not at the local office as he was in Seoul to participate in a memorial ceremony of a former lawmaker.

Chung claimed to be a younger brother of a renowned documentary writer, according to police.

After bounding one of Moon's aides with tape, the offender poured paint thinner on the floor of the office and threw a fire extinguisher out a window.

He demanded that Moon be arrested, but his exact motive is still being investigated.

The one-hour long hostage situation ended without any casualties, as the offender turned himself in to the police outside the building.

"Everything is done now. I will tell everything at the police station and prosecutors' office," he said.

Police said they will investigate the details of the incident, including the reason he committed the crime. (Yonhap)