At least four people have died in massive floods sweeping across the southern states of America.

Torrential rainfall and thunderstorms have caused the Mississippi River to burst its banks.

Officials in Louisiana have warned that "the crisis is not over" and say thousands of homes have already been damaged.

Meanwhile, the National Weather Service in the US is warning of further heavy rain in the lower Mississippi Valley; widespread rain for a majority of the eastern part of America and flash flooding in Oregon and parts of northern California.

DAM BREAK REPORTED ON BAYOU LAFOURCHE BORDERING CALDWELL AND RICHLAND PARSH. WATER FLOWING RAPIDLY TOWARDS HEBERT !!! EVACUATE HEBERT NOW !

— NWS Shreveport (@NWSShreveport) March 14, 2016

Monday's weather map from the National Weather Service shows further heavy rain in the lower Mississippi Valley