A mother and her child are among the most recent casualties of a tornado that hit Oklahoma City on Friday.

According authorities, the mother and her child were killed when the vehicle in which their traveled was picked by the violent thunderstorms.

The highway in which they traveled, Interstate 40, just west of Oklahoma City, was closed after the incident, but not before several crashes were registered due to the storm, said Betsy Randolph, spokeswoman for the Oklahoma Highway Patrol.

Parts of the Oklahoma City metropolitan area were declared under tornado emergency by the National Weather Service meteorologists.

According to spotters, one twister touched down on Interstate 40 and was headed toward Oklahoma City. A tornado also touched down in Moore, which was hit by a massive EF-5 twister last week that killed 24 people.

"The Interstate is at a standstill," Randolph said. "We are begging people to get off the Interstate and seek immediate shelter ... We are in a dire situation."

 "Motorists stuck on any freeway in the path of a twister should try to go in the opposite direction to where the twister was coming from," warned Oklahoma Governor Mary Fallin during an interview to CNN..

"What we saw from the tornadoes that came through Moore and the other ones last week was that people who were in cars on the Interstate were killed," he.added.

Moore Mayor Glenn Lewis told CNN it was "unbelievable" that Moore had been hit again.

Scientists with the National Weather Service, said it was difficult to know exactly how many tornadoes had touched down, but three major storms were potentially producing tornadoes throughout the center of the state.

According to KWTV, a local station, the Oklahoma City airport was closed down and it has turned into a shelter for 1,200 people and about 53,000 people in the Oklahoma City area are without power.

Storms in Oklahoma and Arkansas on Thursday left an Arkansas county sheriff dead and at least one man missing in an attempted water rescue, while at least seven other people were injured elsewhere, officials said.

The body of Scott County Sheriff Cody Carpenter was recovered early on Friday, said Keith Stephens, a spokesman for the Arkansas Game and Fish Commission. Authorities continued to search for a missing state game warden after Thursday night's rescue attempt along the Fourche La Fave River.

A man died in Tull, Arkansas, when a tree fell on his car during a possible tornado, said Grant County sheriff's chief deputy, Pete Roberts. A Scott County official said a woman's body was found in floodwaters on Friday.

Large, long-lasting thunderstorms known as supercells are responsible for producing the strongest tornadoes, along with large hail and other dangerous winds.

Tulsa, as well as Springfield, Missouri, may all be buffeted by Friday's severe weather and possible tornado touchdowns, said Rich Thompson, a lead forecaster at the National Weather Service's Storm Prediction Center in Norman, Oklahoma.

The danger zone included Joplin, Missouri, he added. Joplin was hit by a monster tornado, one of the most catastrophic in U.S. history, that killed 161 people and destroyed about 7,500 homes two years ago.