LUMBERTON, N.C. (AP) — Authorities have arrested 10 Robeson County volunteer firefighters and accused them of setting fire to abandoned buildings and woods over a year and a half.

News outlets report Robeson County Sheriff Ken Sealey said in a statement Tuesday the firefighters were from the Fairmont Rural and Orrum fire departments, and were involved in a conspiracy to set the fires over the last 18 months.

The sheriff said there are approximately 90 arson-related charges in the investigation with more charges expected.

Sealey said a former Maxton police officer and an N.C. Department of Corrections officer were among those arrested.

Sealey’s statement didn’t cite a motive. None of those charged have been identified.

Bail for the former police officer corrections officers is set at $200,000. Bail for the others is $100,000.

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