At least three people were killed by tornadoes in the Midwestern US state of Missouri, Gov. Mike Parson said Thursday.

"There was a lot of devastation throughout the state," Gov. Mike Parson said in a press conference. "We were very fortunate last night that we didn't have more injuries than what we had, and we didn't have more fatalities across the state."

"But three is too many," the governor said.

On Wednesday night, three people died when tornadoes rolled through Golden City, located about 100 kilometers (62 miles) southwest of Jefferson City, the state capital, where a tornado caused extensive damage.

At least 29 tornadoes were detected over a 24-hour period, most of them in Missouri and Oklahoma, while at least 171 have been spotted since last Friday.

"Our hearts go out to the people of Missouri as they woke up to assess the damage from storms. You are strong and resilient, and we are here to assist," President Donald Trump said in a Twitter post.

The president urged residents to "listen to the warnings of your local officials and stay safe. We are with you!"

Meteorologists warned that conditions remain favorable for tornado formation from Kansas City, Missouri, to Lubbock, Texas, and even from Columbus, Ohio, to Philadelphia, Pennsylvania.

Officials in Webber Falls, Oklahoma, ordered the evacuation of residents due to flooding caused by the Arkansas River.

Emergency services workers transported about 20 people to hospitals in Jefferson City, but no one had life-threatening injuries, officials said.

The worst damage in Missouri's capital occurred in a nearly five sq. kilometer (1.9 sq. mile) area in the southern part of the city in which several buildings, including a school, were damaged by the twister's powerful winds.

Parson ordered non-essential state employees in the Jefferson City area to stay home on Thursday.

The governor thanked first responders for their work in the wake of the tornadoes.

"In a time of tragedy, Missourians once again came together and supported and cared for their neighbors, and our first responders acted with speed and skill to rescue survivors," Parson said in a statement.

The National Weather Service (NWS), meanwhile, said it was conducting a preliminary tornado damage survey on Thursday.