Houston, April 29 (IANS) At least four people have been killed since Saturday night when multiple large tornadoes began to hit Oklahoma in the US, Oklahoma Governor Kevin Stitt has said at a news conference.

In the hardest-hit town of Sulphur in Murray County in south Oklahoma, a person was killed and some 30 others injured in the wake of at least two large tornadoes, which flattened a number of homes and buildings, Xinhua news agency quoted Stitt as saying on Sunday.

A flood warning was also issued for the city, according to the National Weather Service.

"It seems like every business downtown has been destroyed now here in Sulphur," Stitt said. "It's definitely the most damage since I've been governor that I've seen."

Two others, including an infant, died in the Holdenville city, where at least 14 homes were damaged or destroyed.

The fourth died near an interstate road, local media reported.

Nearly 47 million people are at risk for severe weather on Sunday when storms continue threatening more twisters, heavy rain and large hail from Missouri to Texas, said the reports.

"In addition to the severe weather, intense rainfall rates are expected to accompany these thunderstorms at times, leading to a moderate to locally high potential of flash flooding," the National Weather Service said.