Story highlights Garland police say four fatalities were likely related to the tornado

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(CNN) At least eight people were killed in the Dallas area during Saturday's outbreak of storms, authorities said.

Officials believe four deaths were related to vehicles struck by a tornado that touched down in the southeast part of Garland, police spokesman Officer Joe Harn said.

Details on the fifth death were not immediately available.

There were three additional deaths in Collin County, said Chris Havey, a spokesman for the sheriff's office. He declined to release any more information until authorities can fully assess their situation.

Preliminary number

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