OKLAHOMA [US], The US state of Oklahoma was hit by severe storms and high winds over the weekend as a series of tornadoes swept across the Great Plains, killing at least four people including an infant, CNN reported. Officials are warning of the threat of more storms, heavy rain and large hail across states from Missouri to Texas on Sunday. Several large and extremely dangerous tornadoes struck parts of Oklahoma overnight Saturday, according to the National Weather Service. There were deaths. in Holdenville, and a third near Marietta on I-35, according to Kelly Cain, public affairs director for the Oklahoma Department of Emergency Management and Homeland Security. At a news conference Sunday, Gov. Kevin Stitt said the fourth death was in Sulphur, the hardest-hit town in Murray County, Oklahoma. There were also reports of injuries, property damage, flooding and downed power lines and trees in several counties on Saturday.overnight, the Oklahoma Department of Emergency Management said, CNN reported. The weather service confirmed 22 tornadoes in the Norman area. Tornadoes of at least EF-3 strength touched down in Sulfur and Marietta Saturday night, according to the weather service. The EF-3 rating indicates wind speeds of 13 mph or more. Governor Stitt said, "It seems as if every trading town here has been destroyed in the sulphur." "This is definitely the most damage I've seen since I've been governor. Stitt said about 30 people were injured in Sulphur, and their conditions are unknown, as CNN reported. He also issued an emergency disaster declaration and announced he would tour storm damage in Sulphur, N. Holdenville, after at least two large tornadoes overnight touched down in Sulphur, which is about 80 miles south of Oklahoma City. Injuries and damage were reported. Subsequently, a flood warning was issued for the city "A large and extremely dangerous tornado was located south of Sulphur, moving north at 35 mph. First responders immediately responded to additional tornado impacts. "Need to get ready!!!" The weather service in Norman warned that about 47 million people are at risk of severe weather from East Texas northward to the upper Mississippi River Valley on Sunday, as communities in Nebraska and Iowa surveyed the devastation already left by the storms. CNN reported that the storms were moving eastward across the Southern Plains, Texas, including cities including Dallas and Austin; Oklahoma City and Tulsa in Oklahoma; Wichita and Topeka in Kansas; And the Kansas City metropolitan area could see severe tornadoes, with more than 4 million people under a tornado watch Sunday night, according to the Storm Prediction Center. Storms could drop hail the size of ping pong balls and Wind gusts up to 70 miles per hour can cause damage.The weather service reported two tornadoes crossing Oklahoma's Highway 9 between Goldsby and Blanchard. Amidst the situation, the University of Oklahoma's Norman warned students and staff to "shelter inside the building you are in. Move to the Lowes floor/interior room." In the second incident, during Friday's severe weather outbreak in Minden One person has died after a tornado struck Iowa, CNN reported, citing Pottawattamie County Emergency Management. A total of four people suffered storm-related injuries, while three people were treated and released Friday in Pottawattamie. A fourth person initially listed in stable condition later died of injuries, said county spokesman Craig Carlson. Iowa Governor Kim Reynolds issued a disaster proclamation for Pottawattamie County in response to Friday's severe weather.