The road sank late Tuesday afternoon and efforts are on to repair the damaged portion to restore traffic on the highway - the only all weather road linking Kashmir with rest of the country, the officials said.
The 270-km highway was closed on Monday following major landslides triggered by incessant rains and snowfall, leaving hundreds of Jammu-bound vehicles stranded.
"The damaged section of the highway was restored with concreting and Granular sub-base (GSB) laying. The concrete needs 8-10 hours for consolidation," Deputy Commissioner, Ramban, Showkat Aijaz Bhat said.
After setting of concrete, he said vehicles would be allowed to ply on the highway.