According to the department.
Many of the victims were reportedly suffering from chronic or respiratory related diseases ar the time the cold weather hit. Some of them were found dead after drinking alcohol.
In Nan, the temperature plunged to below 10C Wednesday and some schools in mountainous areas there were temporarily closed.
Chatchai Taptimon, head of Nan Primary Education Service Office 2, ordered schools to remain cloesd until Thursday as a precautionary measure.
Students needed to keep warm beside a bonfire at home, he said.