Original: The lake flooding has displaced 6,000 people from upstream villages, stranded (from land transportation routes) a further 25,000, and inundated over 12 m of the Karakoram Highway.
Simplified: The lake flooding has forced 6,000 people to move from upstream villages, stranded (from land transportation routes) a further 25,000, It inundated over 12 m of the Karakoram Highway.