At least 40 people have died across Missouri, Arkansas, Texas, Oklahoma, Kansas, Alabama and Mississippi as powerful storm systems swept through the U.S. Midwest and the South, NBC News reports.

The deadly storms that ravaged much of the South and the Midwest U.S. this weekend are heading east.

According to preliminary reports, at least 557 storms were reported Friday and 135 were reported yesterday.

At least 32 of Friday’s storms and 34 of yesterday’s storms were tornadoes, per reports.

The storms have caused deaths linked to wildfires in Oklahoma, where over 100 people were injured, injured dozens in Arkansas and left hundreds of thousands of customers without power.

U.S. President Donald Trump said he was following the situation. He activated the National Guard in the tornado-ravaged Arkansas.