The death toll following a serious weekend road accident near the town of Hameln has risen to four after the 20-year-old driver succumbed to his injuries in hospital, police in the German state of Lower Saxony reported on Tuesday. Three young adults died at the scene of the accident, and a 17-year-old from the town remains in hospital in stable condition. The car they were in left the road near Humboldt Lake in Salzhemmendorf on Sunday afternoon for reasons that remain unclear and hit a tree. No other vehicle was involved.