Harvey lashes Texas and Louisiana as officials warn 30,000 people will need shelter

• Police chief says 2,000 people already rescued from heavy floods
• Millions of Texans stranded in their homes awaiting help
• It's a fact: climate change made Hurricane Harvey more deadly
• Tropical storm Harvey - live updates

The full scale of the disaster unfolding in Houston and across large parts of Texas and Louisiana was emerging on Monday, as authorities warned that 30,000 people would be forced to seek shelter from an epic deluge of historic proportions.

The official death toll from the catastrophe now stands at eight, though the figure could rise substantially as flooded neighborhoods are cleared. KHOU reported that six of the dead were believed to have come from a single family, after an elderly couple and their four great-grandchildren aged six to 16 were trapped inside a white van that was engulfed in the flood waters.