ST. LOUIS (AP) — A man and his two adult sons died when a sudden, powerful storm slammed into a mobile home in southeast Missouri, officials said Tuesday as weather officials began to investigate if the damage was caused by a tornado or straight line winds.

The storm struck Missouri, Illinois and Kentucky late Monday, but hit hardest in the tiny southeast Missouri village of Diehlstadt, about 100 miles south of St. Louis, where the three men were killed.

The Missouri State Highway Patrol said 70-year-old Loy Miller, the owner of the trailer, and his sons, Jasper Miller, 50, and Randy Miller, 48, were killed. Patrol Trooper Clark Parrott said it wasn't clear if the sons also lived in the mobile home.

"We had a pretty intense, concentrated storm," Parrott said.

The only reported injury was an 11-year-old St. Louis County girl who had minor head and arm injuries after being pelted by huge chunks of hail.

The gusty storm developed in the St. Louis area Monday afternoon, producing nearly an inch of rain and ping-pong-sized hail in some places while leaving others bone dry, National Weather Service meteorologist Chris Sanders said. Hail, about an inch of rain and winds stronger than 50 mph were also reported in parts of southern Illinois and northwestern Kentucky.

The storm became particularly intense in southeast Missouri and Diehlstadt, a town of 163 residents in Scott County, took the worst of it. Parrott said two other homes and five sheds were damaged, and downed power lines closed Highway 77 for several hours. Power was restored before dawn.

A team from the National Weather Service was in the Diehlstadt area Tuesday to determine if the damage came from straight-line winds or a tornado. Parrott said he was unaware of any funnel cloud sightings.

The storm was very much hit-and-miss. In the St. Louis area, Chesterfield on the east side of the Missouri River saw a downpour of sideways-blowing rain and hail around 4:30 p.m.; Weldon Spring, on the other side of the river, was virtually dry.

Monday's storm was so spotty that it did virtually nothing to relieve moderate to severe drought conditions in the area.

"We need a couple of inches of rain, big-time," Sanders said. "Heading into May we were above normal rainfall, but May just really killed it."

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