At least three workers were feared trapped on Thursday after water and debris entered an under-construction tunnel at a hydroelectric project site in Chamoli district of Uttarakhand, officials said.

Police, the district administration and several agencies are carrying out the rescue operation at the Tehri Hydro Development Corporation (THDC) Limited project site in the Pipalkoti area.

Teams from the State Disaster Response Force (SDRF) and Central Industrial Security Force (CISF) are also involved in the operation.

16 workers brought out safely

According to information released by the state government, around 18 to 19 workers were trapped inside the tunnel at about 7pm.

So far, 16 workers have been safely rescued, while efforts are continuing to bring out those still inside.

The rescue operation remains underway at the project site as teams work to reach the remaining workers.