BELLE FOURCHE - The city of Belle Fourche has spent about $22,000 to buy a ground-penetrating radar unit to uncover unmarked gravesites.

The Black Hills Pioneer reports that the city purchased the radar in January and started using it within the last few weeks.

The city is also creating a database of unmarked graves.

Many of the unmarked graves have been discovered as workers prepare to dig new gravesites. In 2012, city crews found 10 graves while digging new plots.

Dirk Hoffman, the city's public works director, says many of the graves could be from the 1920s and 1930s. He says the city was overwhelmed with the effects of the influenza pandemic of 1918 and 1919.

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