Storm's damage could exceed $20 million.

Byline: Lynn Horsley and Brad Cooper

KANSAS CITY, Mo. _ Government officials estimated Monday that more than 1,000 structures were damaged or destroyed Sunday in the strongest wave of tornadoes to roar through the area in 26 years.

Losses could exceed $20 million.

The governors in Kansas and Missouri each asked President Bush to declare hard-hit areas of their states disaster areas, beginning the process to try to qualify for federal disaster assistance.

Gov. Bob Holden asked Bush to declare 39 Missouri counties disaster areas. Eighteen deaths were reported in southern Missouri. Widespread losses were reported in 17 Missouri counties, including Jackson, Clay, Platte and Cass.

Holden also called up 175 National Guard soldiers to emergency duty Monday, 20 of whom will provide security in Gladstone.

Kansas Gov. Kathleen Sebelius declared a disaster area in seven counties, including Wyandotte, Leavenworth and Miami counties in the metro area. Seven persons died in Kansas, including one in Wyandotte County, and at least 50 were injured. At least 600 structures were damaged in Wyandotte County.

On Monday afternoon, Sebelius toured shattered sites in Wyandotte County by helicopter and met with residents who lost homes.

"In this area, as well as in southeast Kansas, you really see the devastation up close and personal ... you can tell where there were houses, where there were…