(CNN)Cleanup crews on Thursday started assessing the damage caused by storms that slashed across Oklahoma on Wednesday, killing one person and injuring about two dozen others across the state. A reported tornado ravaged a mobile home park, destroying dozens of trailers just west of Tulsa in the suburb of Sand Springs. Authorities said the man who died at the River Oaks Mobile Home Park had been trying to help his father, who was injured, according to CNN affiliate KJRH. One woman at the mobile home park told KJRH that she was cooking when the storm hit. "Within 5 minutes it was dark and the sirens were going off and you couldn't hear yourself think," Brandy Richards said. "And you just grab the kids and we ran across the street. My best friend has the only house that's back there, and we barely got into the house and it took the garage. It was so fast." "It looks like there's been a little war zone around here," Tammi Hart told CNN affiliate KTUL. The storm flattened a Sand Springs gymnastics studio, where 60 kids and adults were huddled underground. "We were just in the middle of practice and the sirens started going off and we just had to get all the kids to the basement," according instructor Kelsey Haggard, who said she heard a "big boom" when the building was hit. "Just really happy everyone got out safe," said Haggard. "It was really scary ... it just seems so surreal." In addition to the death at the mobile home park, KTUL reported two other people were taken to the hospital in critical condition. The Oklahoma State Department of Health said two dozen people were injured across the state, according to CNN affiliate KOKI. Storm damage was reported across the Tulsa metro area. Gov. Mary Fallin toured the damage in Sand Springs on Thursday and declared a state of emergency for 25 counties. "Our hearts and prayers go out to the family that lost a loved one and certainly to those who were injured or lost their home or business," she said. Severe weather also tore through the Oklahoma City area, including Moore, which has seen more than its share of devastating storms. A massive tornado hit Moore nearly two years ago, killing 24 people and injuring hundreds of others. The Moore Police Department said a 2-mile square area had significant damage, mainly roofs off homes and downed trees. Trees had to be cleared so law enforcement and emergency vehicles could get through. "You know, this isn't the first time we've done this so ... unfortunately, we've gotten pretty good at getting people back into their residences as quick as we can," said Sgt. Jeremy Lewis with the city's police. Until Wednesday, there hadn't been a single report of a tornado in the United States during March. CNN meteorologist Judson Jones said there were preliminary reports of seven tornadoes on Wednesday. An average year would produce 80 twisters in March, he said. March is typically a transitional month, where warm moist air from the Gulf of Mexico collides with cold Arctic air to produce severe thunderstorms and tornadoes. This year, however, the jet stream pattern responsible for all the cold air and snow in the East had remained stuck in more of a winter mode. But that changed this week as an Arctic cold front began crashing to the south, bringing together the stormy mix. CNN's Sean Morris, AnneClaire Stapleton, Jeremy Grisham and Dave Alsup contributed to this report.
"It looks like there's been a little war zone around here"
National Weather Service:  There are preliminary reports of 7 tornadoes . "It looks like there's been a little war zone around here," Oklahoma resident says .