SEOUL - Four workers were killed and six others were injured Tuesday after a bridge collapsed in South Korea's highway construction site, according to the fire authorities.

The structure, comprising four or five plates placed on top of the bridge, collapsed at the highway construction site in Anseong, some 65 km south of Seoul, at around 9:49 am local time (0049 GMT).

Of 10 workers who fell to the ground and were buried under rubble, four were confirmed dead. Five others suffered serious injuries, and one was slightly wounded.

The collapse took place while using a crane and connecting the top plates between piers.

The fire authorities mobilized 92 pieces of equipment and about 170 personnel for rescue operations.