The first batch of severe weather in the US tornado season has devastated an Oklahoma mobile home park, as storms across the area damaged buildings, tore off roofs and left debris strewn across roads.
Tens of thousands of Oklahoma residents were without power as officials assessed the damage.
Tulsa County Sheriff's Captain Billy McKelvey said one person was killed in the mobile home park, which he said could accommodate 40 to 50 trailers.
The Oklahoma Department of Emergency Management said it had reports of nine people taken to hospitals. Mr McKelvey said he believed at least 15 people were hurt.
Tornadoes were seen elsewhere in Oklahoma, as well as neighbouring state Arkansas.
The tornado season usually ramps up for parts of the US in March, but until Tuesday, when a waterspout formed over an Arkansas lake, the country had not had a tornado in more than a month.
Weather patterns this month funnelled cold air into much of the country, depriving the atmosphere of the warm, moist air necessary for forming bad storms for most of the month.