Prime Minister Lee Nak-yon called for immediate steps to make sure school classrooms are free of asbestos, following reports that traces of the cancer-causing material were found in many classrooms even after removal of asbestos-containing construction material from them.

More than 1,200 schools across the country have so far carried out projects to rid classrooms of construction materials containing asbestos, a once popular substance for insulation. But traces of asbestos were still detected even after the work.

"The education, labor and environment ministries are jointly carrying out an inspection into whether asbestos still remains at 1,226 schools that have carried out asbestos-removal projects, and asbestos was found in many of them," Lee said during a weekly government policy coordination meeting. 

"The government should immediately take the necessary steps to protect students' health," he said. "All problematic classrooms should be shut down and meticulous cleaning should be done before testing the air quality with parents in attendance."

Lee said that all such measures should be completed before the end of the upcoming Chuseok holiday.

Lee also instructed officials to look into why asbestos remnants still remain in classrooms even after cleaning was done following the asbestos removal work, and punish those responsible if any irregularities are found. (Yonhap)