A father and son have been charged with kidnapping two federal biologists at gunpoint in Northern California’s Shasta-Trinity National Forest.

Prosecutors allege Joseph Henrichsen, 49, used an AR-15-style rifle to restrain the Forest Service employees while his 23-year-old son, Phoenix, assisted during the hourslong incident.

The victims were held at a trailer and allegedly threatened before negotiators secured their release and the suspects surrendered.

Authorities have not identified a clear motive but said the investigation is ongoing, with past legal issues involving Joseph also being reviewed, NBC News has reported.

Both men face federal kidnapping charges that could carry a sentence of life in prison if convicted.