Cheonan: Four workers were killed and six others injured Tuesday when part of a bridge under construction collapsed on a highway in Cheonan, 90 kilometers south of the Korean capital, Seoul.

According to Qatar News Agency, four or five-long steel beams holding up the bridge collapsed one by one during construction work, killing four people and injuring six others, most of them seriously, South Korea’s Yonhap News Agency reported, citing local authorities. The workers were constructing a section of the Seoul-Sejong road expressway.

Last February, six people were killed and seven others injured in a fire that broke out at a resort construction site in the coastal city of Busan in South Korea.