Johannesburg, Jumada I 03, 1436, February 22, 2015, SPA -- Eighteen workers at a South African gold mine are trapped underground after a fire broke out Sunday, the company that operates the mine said according to dpa. Of the 486 miners working at the Kusasalethu mine near Carletonvilleat the time, 468 have been rescued and brought to the surface, a spokeswoman for the Harmony Gold Mining Co said. The company has contact with the miners remaining below and none of them is known to be injured, she said. Rescue workers are trying to reach them, but they are in an area that is difficult to access, the spokeswoman said. "We simply need time to get all the miners out," she said. The fire, which has been contained, is believed to have started during maintenance on an air cooler 2,300 metres below ground, Harmony Gold Mining said. All work at the mine besides the rescue operation has been suspended, the company said. South Africa, the world's fourth-largest gold exporter, has some of the world's deepest gold mines, which increases the risks for miners. --SPA 23:45 LOCAL TIME 20:45 GMT www.spa.gov.sa/w