LAKE ANDES, S.D. (AP) — A South Dakota man accused of driving drunk and killing two federal wildlife researchers more than a year ago is on trial in Charles Mix County.

Thirty-year-old Ronald Fischer Jr., of Lake Andes, has pleaded not guilty to manslaughter and vehicular homicide charges. His trial began Monday. He could face life in prison if convicted.

Fischer was allegedly driving under the influence of alcohol and marijuana on July 8, 2013, in the Pickstown area when he failed to stop at a stop sign. Authorities say his vehicle went into a parking lot, where it struck and killed 25-year-old Maegan Spindler, of Cazenovia, New York, and 46-year-old Robert Klumb, of Pierre.

The two U.S. Fish & Wildlife Service employees were in the area conducting tests on the Missouri River.

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