A coal mine gas leak left at least 43 people trapped underground in southwest China\'s Yunnan Province Thursday, local authorities said. The accident took place at about 6:25 a.m. at the Sizhuang Coal Mine in Shizong County, Qujing City, the Yunnan Provincial Emergency Response Office announced in a statement. A rescue operation has been launched, the statement said. The Qujing municipal government had earlier referred to the accident as a \"gas explosion.\" The exact number of miners working underground is still being checked.