At least 18 people were killed on Saturday in Missouri and Oklahoma after tornadoes swept through the area, authorities in the two states said.

There were at least 12 storm-related deaths in Missouri, 10 of those in Newton County on the border with Oklahoma, according to Susie Stonner of the Missouri Emergency Management Agency.

"There's a lot of wreckage and overturned vehicles," she said, adding police had not ruled out finding more victims.

Hardest hit was Racine, a tiny community in Newton County about 170 miles south of Kansas City.

Six people were also killed in the small northeastern Oklahoma town of Picher, officials said.

"Basically a 24-block area is virtually destroyed," said Michelann Ooten, a spokeswoman for the Oklahoma Department of Emergency Management.

She added that Oklahoma Gov. Brad Henry had ordered National Guard troops to arrive in Picher by Sunday morning to help in rescue and recovery operations.

Local television footage from Picher showed widespread devastation. Homes were ripped from their foundations, trees were stripped of leaves and sheet metal was twisted like paper.

Ooten said search efforts for missing people in Picher were shutting down as it was unsafe for rescuers to move through the rubble at night even with mobile floodlights.

"You need day break," she said. "That'll be the real story."

Fifty people have been treated for injuries ranging from head trauma to lacerations and broken bones, said Jennifer Hessee, spokeswoman for the Integris Baptist Regional Health Center in Miami, Oklahoma, 15 miles from Picher.

"I've never seen anything like this," Hessee said. "We went into disaster mode and called in all of our staff. It's slowed down. Hopefully the worst has come in. It'll make for a sad Mother's Day for a lot of people."

Picher is at the center of a massive federal clean-up of pollution from lead and zinc mining. Residents were being assisted with relocation from the community after high levels of lead were found in groundwater.

Many homes destroyed

In Missouri, Howard Birdsong, the mayor of Neosho, a town of 11,500 that is the Newton County seat, said at least two of the deaths came when a tornado overturned a vehicle.

It appeared the twister carved a 15-mile (25-km) path just north of town after striking neighboring Oklahoma. In some areas, the destruction is a half-mile wide, he said.

"There's an awful lot of property damage," Birdsong said by telephone. "From what I've seen many homes have been destroyed, some businesses, and some cars have been overturned, uprooted trees and power outages ... There are several dozen injured."

In Barry County, a person was killed in Purdy, where several trailer homes, a church and other residences were damaged, the National Weather Service said.

A tree collapsed a trailer home in Carthage, in Jasper County, killing one person, it said.

In all, the National Weather Service's Storm Prediction Center in Norman, Oklahoma, recorded 34 tornado reports in Missouri, Oklahoma, and Arkansas, though some were multiple reports about the same twister or twisters.

The National Weather Service in Springfield, Missouri, said it would send out assessment teams on Sunday morning to determine the scope of the damage, and figure out the number and paths of the tornadoes.

PHOTO CAPTION:

Turnado kills 18

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