A mountain river swollen by monsoon rains has swept away the main bridge linking Nepal with China. The flooding Tuesday also swept away 18 people, and rescue efforts were underway.

Nepal’s mountainous terrain is vulnerable to flash floods. Disasters have gotten deadlier in recent years in part because of changing climate patterns. Erratic rainfall, floods, landslides, avalanches and glacial lake outbursts are becoming more serious.

According to National Disaster Risk Reduction and Management Authority (NDRRMA) Director General Dinesh Bhatta, the flood might be caused by the outburst of a glacial lake situated near the Nepal-China border, as there was no excessive rainfall at that time on both sides of the border.