The incident occurred on the section of the road from Cam Pha to Ha Long. Large rocks detached from the mountainside near the sidewalk and tumbled onto the road.

Local authorities reported the incident at 3:30 p.m., stating there were no casualties or damage to vehicles. However, some trees and signs were crushed and damaged.

The scene of the rockslide onto the coastal road. Photo: Provided by a local resident

The initial assessment suggests the cause may have been lightning strikes or weathering, combined with the heavy rain over the past few days. That afternoon, the Ha Long - Cam Pha area experienced thunderstorms and lightning due to the influence of a typhoon.

Authorities implemented traffic diversions and mobilized machinery to clear the rocks to ensure safety for passing vehicles.

A month earlier, on the same stretch of road in Quang Hanh ward, three rocks weighing tens of tons also fell onto the road.

The 18.7 km, six-lane Ha Long - Cam Pha coastal road connects Ha Long Bay with Bai Tu Long Bay and reduces traffic on National Highway 18. This modern coastal tourist route passes through many mountainous and rocky areas, posing a risk of landslides.

Le Tan