The US city of Houston has declared a night-time curfew as it battles the impact of Hurricane Harvey. <br/><br/>The storm has dumped record rainfall, leaving large parts of the city underwater, homes destroyed and over 20 people reported dead. Houston mayor Sylvester Turner said, the curfew will help prevent property crimes against evacuated homes, and was in force only to prevent potential criminal acts. <br/><br/>City officials have reported instances of looting, armed robberies and of people impersonating police officers. <br/><br/>Thousands of people have fled their homes in search of emergency shelter amid severe flooding. <br/><br/>The National Weather Service said, the rainfall in Texas set a new record for the continental US and recorded 51.88 inches of rain since Friday. More than 13,000 people have been rescued in the affected areas. <br/><br/>President Donald Trump has already declared a federal state of emergency in both Texas and nearby Louisiana, where Harvey is expected to make landfall again today.<br/><br/>The move releases emergency government funding and other assistance.