At least 24 people have died in Missouri, Arkansas, Illinois and Oklahoma in the recent flooding and t widespread evacuations continue, according to media reports. Many of the victims were trapped in cars while driving onto swamped roadways.

Fourteen deaths occurred in Missouri, where Gov. Jay Nixon declared a state of emergency and the national guard were called in to assist aid operations.

“Rivers are continuing to rise to historic levels and these citizen-soldiers are providing vital assistance to communities – including providing security in evacuated areas and augmenting flood-fighting efforts,” Nixon said in a statement.

The casualties in Missouri include five international soldiers who were in Fort Leonard Wood as part of a training program.

Rising water on the Mississippi River and its branches forced the closure of interstates 55 and 44 near St. Louis, Missouri, local media said, as floodwaters began to move downstream, setting up threats of more flooding in the region.

The Weather Channel described the situation a “slow-motion disaster”, as many rivers have yet to crest in some areas and swelling waterways increase the danger of exacerbating the disaster.

Meteorologists said flooding along some tributaries could send the Mississippi River to levels not seen since the Great Flood of 1993 that left 50 people dead in several Midwestern states.

Mississippi Gov. Phil Bryant took to Twitter to ask President Barack Obama to declare a major disaster declaration for affected areas “ahead of Mississippi River flooding ahead in the coming days”.