Daejeon: Four people were killed and two others injured Monday in an explosion at defense company Hanwha Aerospace's factory in the central city of Daejeon, officials said. Authorities received a report of the explosion at 10:59 a.m., and they are working to confirm the exact number of casualties.

According to Yonhap News Agency, fire authorities dispatched to the scene are working to extinguish a blaze at the site. The explosion is believed to have occurred on the first floor of the factory. Police and fire officials plan to investigate the exact cause of the incident once the blaze is put out.