Sixty-two pupils and a teacher have been discharged from hospitals and returned to school, while three other students still remained hospitalized in northern Inner Mongolia Autonomous Region on Friday as a result of a carbon-monoxide poisoning.

The three students are in stable condition at a local hospital, said a spokesman with the Inner Mongolia Autonomous Regional Health Bureau.

The pupils and teacher of the Niuchang Primary School in the Yuquan District in the regional capital reported dizziness, headaches and nausea after waking up early on Wednesday morning. They were sent to different hospitals.

An initial investigation by the regional disease control center indicated that smoke leaked into the pupils' dorms from a nearby boiler room. The boiler was supplying heat to the dorms.

The local health authority has ordered the school to improve the heating facilities and address the problem.

Early this month, 11 students died of carbon-monoxide poisoning when they used a charcoal stove to warm themselves in a middle school in northwest China's Shaanxi Province.

(Xinhua News Agency December 26, 2008)