Three workers have been killed and another injured after water flooded a tunnel at the Thuan Hoa Hydropower Plant in northern Vietnam, local media has reported.

The workers, who were of Chinese nationality, were involved in the project construction and were working inside a water transmission tunnel, Vietnam news agency said. Work at the site has now been suspended while investigations are underway.

The 38MW hydro plant has been under construction since 2013, with work scheduled for completion in 2016