ARLINGTON, Va. (Dec. 31, 2015) -- At least 625 National Guard Citizen-Soldiers and airmen are on duty Thursday as several southern and central states fought flooding triggered by rain and runoff.

In response to historic flooding in some areas of the state, Gov. Jay Nixon mobilized the Missouri National Guard to protect local communities and support emergency response personnel.

The toll so far: At least 20 people dead over several days in Missouri and Illinois, the Associated Press reported.

States of emergency have been declared in these states: Georgia, Texas, New Mexico, Missouri, Arkansas, Oklahoma, Illinois, Louisiana and Missouri, according to data from the National Guard Bureau.

By far, Missouri had the most Guard personnel on duty: about 515 Guard figures showed. The Guard there mobilized a task force with several hundred Soldiers and airmen in several different locations across the state to provide defense support of civil authorities by saving lives, protecting property, and maintaining order, said Maj. Gen. Steve Danner, adjutant general of the Missouri National Guard.

About 50 troops are on duty in New Mexico and 54 in Oklahoma for weather-related assistance. The Iowa National Guard has agreed to provide support to Missouri personnel, but hasn't deployed anyone yet.

"The Citizen-Soldiers and airmen of the Missouri National Guard are once again ready to support fellow Missourians in need," Danner said."We will provide the same high-quality emergency response they've come to expect."

Missouri National Guard liaison officers are at emergency operations centers in Perry, St. Charles, Cape Girardeau, Jefferson, St. Louis and Franklin counties, where the flood stage of the Mississippi River is expected to exceed the 1993 record levels in the coming days.

While on duty, Missouri Guard members are expected to take on a number of missions in support of local authorities, to include directing traffic away from road closures, providing security around breached levees and evacuated areas, sandbagging, levee monitoring, Danner said.

"We have a team of seasoned leaders who are well versed in responding to state emergencies," Danner said. "Your Missouri National Guard has supported 14 state emergencies since 2009, including major flooding in 2011."

The evacuation of West Alton has already taken place as a result of the flooding. Hundreds of roads have been closed across Missouri, including in St. Louis and all lanes of I-44 at Jerome near Rolla. In addition, 124 areas on rivers in Missouri are in various flood stages.

Local officials in Perryville have been working with the U.S. Army Corps of Engineers to fortify the Bois Brule levee on the Mississippi River to protect area homes and businesses, including Sabreliner Corporation and Gilster-Mary Lee.

The troops are part of a task force organized under the 35th Engineer Brigade on Fort Leonard Wood with Lt. Col. Paul Kirchhoff as the task force commander. Other units supporting the flood response include 70th Troop Command and 157th Air Operations, Jefferson Barracks in St. Louis County; 205th Military Police Battalion, Poplar Bluff; 1140th Engineer Battalion, Cape Girardeau; and the Joint Operations Center at Joint Force Headquarters in Jefferson City.

Missouri's Citizen-Soldiers and airmen will continue working in support of local authorities until released by Nixon. The Missouri National Guard has a total force of more than 11,800 Guard members who are ready to respond.