The worst storms to slam southern US states in years flattened buildings and overturned vehicles, with intense tornados and floods leaving a trail of destruction and 190 people dead.
The severe weather killed 128 people in Alabama on Wednesday alone, authorities said, and President Barack Obama said Washington would be rushing assistance to the battered southeastern state.
States of emergency were declared in Alabama, Arkansas, Georgia, Kentucky, Mississippi, Missouri, Tennessee and Oklahoma, and governors called out the National Guard to help with rescue and cleanup operations.
The National Weather Service (NWS) had preliminary reports of more than 300 tornados since storms began Friday, including more than 130 on Wednesday alone.
Alabama was especially badly hit, caught by two lines of storms and an evening tornado that tore through the city of Tuscaloosa, home to the University of Alabama.
Tuscaloosa Mayor Walter Maddox told CNN that the tornado had "obliterated blocks and blocks" of his city, leaving 36 people dead there.
Death toll passes 190 as storms ravage US south
