FBI officials have established checkpoints around the Malheur National Wildlife Refuge as a handful of armed militants remain inside. Bradley W. Parks / OPB

As the occupation of the Malheur National Wildlife Refuge enters its 30th day, it appears the FBI may be locking down lines of communication.

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OPB spoke with the remaining occupiers inside the refuge Sunday by cellphone. They say federal authorities have locked down their ability to make or receive calls.

David Fry, one of the four remaining militants, said the FBI made it so the occupiers can't make outgoing calls on their cellphones. Fry said he can receive incoming calls, but that the other three in the refuge appear unable to receive calls on their cellphones. The militants also said they've lost access to the internet.

The militants said they aren't currently inside any of the buildings at the refuge and they've been using a generator so they aren't sure if the FBI also cut power to the buildings.

Sean Anderson, another of the remaining militants inside the refuge, expressed frustration with the FBI's barricade that is preventing media from getting into the refuge.

Repeated calls to the refuge's landline Sunday morning resulted in a busy signal.

OPB has reached out to law enforcement for confirmation.

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