The landslide occurred at around 2.15 am at Km120+900 on National Highway 4D in Ta Phin Commune.
Several large rocks, including at least one weighing several tonnes, fell from the uphill embankment along with soil and debris, completely blocking the roadway.
Traffic police and local authorities arrived at the scene shortly afterwards to cordon off the area, prevent vehicles from entering the landslide zone and install warning signs and barriers.
Emergency crews were deployed with heavy machinery and specialised equipment to break up the boulder and clear debris from the road.
According to Lao Cai’s road maintenance authorities, the affected section had been largely cleared and traffic resumed by around 9.30 am.