Seventeen people were injured, one of them seriously, when a natural gas-powered public transit bus exploded on a Seoul street, police and witnesses said Monday, Yonhap News reported.

 The explosion took place at around 4:57 p.m. when the bus was waiting for the light to change on a motorway in Haengdang-dong of Seoul, police said.


  Police identified the seriously injured as a 28-year-old female passenger of the bus and said 16 other people, including six pedestrians, suffered minor injuries.

  The female passenger had her ankles seriously injured and needed surgery, they said.

   "I heard a loud bang in the bus and black smoke was seen and lasted several seconds," police quoted a witness as saying.

   Television footage showed the lower mid part of the bus partly destroyed. The explosion was powerful enough to break windows of nearby buildings.

   Police suspected that a possible leak in the bus's gas tank might have caused the explosion.

   About 95 percent of public transit buses run by the Seoul Metropolitan Government use compressed natural gas as fuel.

   City officials said they immediately launched checks on the safety of all  gas-powered buses.

   The Ministry of Knowledge and Economy plans to form a task force to investigate the exact cause of the bus explosion. 

  If a defect of  the gas tank in the bus is found to be the cause of the explosion, Yonhap reported, the ministry will recall all CNG buses with gas tanks manufactured in the same year with that of the exploded bus.