Two U.S. Forest Service employees who were kidnapped while working in Northern California — and held at gunpoint inside a rural trailer for more than 12 hours — have been released, officials said Friday. Two suspects, a father and his adult son who were allegedly armed with guns and knives, have been arrested. 

The employees were kidnapped sometime before 11 a.m. local time Thursday while conducting field work in the Shasta Trinity National Forest, U.S. Forest Service Chief Tom Schultz said in a news conference Friday. 

Siskiyou County Sheriff Jeremiah LaRue said deputies received a call from U.S. Forest Service officials that one of the suspects, identified as 49-year-old Joseph Charles Henrichsen, had told authorities that the two employees were zip-tied and being held at gunpoint in a trailer in a rural area outside the small city of Mount Shasta, which is located about 50 miles south of the Oregon-California border.

“Mr. Henrichsen indicated that he had firearms, ammunition, and wanted to speak with the FBI,” LaRue said.

Multiple local and federal agencies responded, including the FBI, and using drones, authorities were able to identify the trailer where the two workers were being held, LaRue said. SWAT, hostage negotiators, a bomb squad and snipers were dispatched to the scene as well.

It took authorities until a little after 4 p.m. Thursday to begin direct negotiations with Henrichsen and his son, Phoenix Henrichsen, the sheriff said.

“We attempted every effort to begin communicating with him to resolve the potential conflict,” LaRue told reporters.

The two workers were finally released from the trailer a little before 2 a.m. Friday, LaRue said. They were not seriously hurt during the ordeal.

About 40 minutes later, the two suspects emerged from the trailer and were taken into custody.

Brian Tosch, acting special agent in charge for the FBI’s Sacramento field office, said that at the time of their surrender, Charles Henrichsen “had an AR-15 and knives, and claimed to have grenades.”

Officials could not confirm if the suspects owned or resided in the trailer where the victims were held. Investigators do not yet have a motive in the kidnapping, Tosch said. The two suspects will face federal charges of kidnapping a federal employee, said Eric Grant, U.S. attorney for the Eastern District of California.

Shasta County Sheriff Michael Johnson emphasized that the remoteness of the trailer presented challenges for law enforcement.

“I’ve got to tell you folks, this is remote Northern California, out in a rural area where it’s tough to get resources in and out, it’s a small one-lane road,” Johnson said. “It is rough terrain and different than handling an incident within a city or urban environment.”

Schultz said the two employees were performing routine work when they were kidnapped.

“They weren’t patrolling there, they were just going to do their work. It was just seasonal work they would do on a regular basis,” Schultz said, describing the incident as a “frightening experience for everyone involved.”

“I want to say how profoundly grateful and relieved that we are that our two employees were released safely,” he said.