SEOUL: A bus plowed into pedestrians after veering off a road in western Seoul on Friday, leaving two people seriously hurt and another 11 injured, rescue officials said.

The intracity bus drove off the road at an intersection near Seodaemun Station at 1:15 pm before ramming into the pedestrians and crashing into a building, according to the officials, Yonhap News Agency reported.

The two people seriously hurt include a pedestrian in her 50s who suffered a broken leg and another 30-something pedestrian who was bleeding from his head. They were moved to the hospital along with six others. Police have not found signs of drunk driving but plan to test the 50-something bus driver, who was also injured, for drugs.

A witness at the scene said the bus was going straight forward before suddenly hitting a car, a motorcycle and people. The woman in her 50s said she heard a loud noise as if on a "battlefield" before fleeing the scene. Authorities plan to investigate the exact cause of the accident.

They are currently working to relocate the bus and have dispatched 271 personnel and 18 vehicles to secure the area. On January 10, five people were killed in multiple accidents on a highway in the southeastern province of North Gyeongsang suspected to have been caused by black ice, authorities said.

One of the accidents happened at 6:20 am near an interchange in the Sangju section of the Seosan-Yeongdeok Expressway, when a truck tumbled out of the road after ramming into a guardrail while trying to avoid a vehicle that had stopped.

The truck driver was killed. Other accidents reported in the area include a sedan crash that killed all four people on board.

Police are investigating whether the accident is connected to another pileup reported in the area involving a trailer vehicle. In another accident, a sport utility vehicle erupted into flames after colliding with a truck and crashing into a guardrail near the interchange at 6:35 am.

As of 11 am, the death stood at five with multiple people injured. Police believe more than 20 vehicles were involved in the accidents. Due to the accidents, traffic on parts of the highway was temporarily restricted.

Authorities are investigating the crashes and suspects they were caused by black ice formed when snow or rain freezes.