In a letter to the country's top law enforcement officials, Gov. Kate Brown pressed for "swift resolution" of the wildlife refuge occupation outside Burns.

Brown also wrote President Obama calling for action "without further delay."

The U.S. Justice Department and the White House did not respond to requests Thursday for comment.

The FBI released a statement Thursday afternoon, saying its response has been "deliberate and measured as we seek a peaceful resolution."

The governor spoke out publicly Wednesday on the need for an end to the takeover that started Jan. 2 and has disrupted life throughout Harney County. Armed protesters holding the headquarters compound of the Malheur National Wildlife Refuge are staying put despite calls from the sheriff and community members to leave.

Brown said in one letter that she talked with FBI Director James Comey about the Oregon standoff. The FBI is in charge of investigating and ending the refuge takeover. In a letter to Comey and to Attorney General Loretta Lynch, the governor recounted how every day "tensions are increasing exponentially" in Harney County.

Document: Gov. Kate Brown's letter to attorney general, FBI director

"While it is easy to assume that an occupation in such a remote location does not threaten public safety and does not harm any victims, that perception is far from accurate," the governor wrote.

Adding to community tensions is that "the criminals on the refuge are allowed to travel on and off the premises with little fear of law enforcement contact or interaction," she said.

The leader of the occupation, Arizona businessman Ammon Bundy, and other key leaders of the group showed up Tuesday evening at a community meeting hosted by local public officials. A phalanx of state, county and city law enforcement officials was stationed both inside the Burns High School gymnasium, a school entryway and the school parking lot during the meeting.

Statement from FBI

The FBI released this statement Thursday afternoon:

"The FBI recognizes that many in the community have questions about why we are here and our role in helping to end the occupation of the wildlife refuge. We are here to work closely with Sheriff Ward and our local, state and federal partners to protect the safety and welfare of this community. This occupation has caused tremendous disruption and hardship for the people of Harney County, and our response has been deliberate and measured as we seek a peaceful resolution."

No move was made to arrest Bundy or others, triggering a social media storm of questions about why they were allowed free passage. Law enforcement officials haven't commented on their tactics or strategy.

Brown noted that besides additional state troopers stationed in Harney County, sheriff's offices and city police departments around Oregon have been rotating in officers to help.

"This is not a sustainable law enforcement model for any extended period of time," she said.

State police last week arrested one occupier on accusations of driving a stolen refuge truck into Burns. Troopers also arrested another man outside Burns on weapons charges after he was stopped and told police he was destined for the refuge to join the militants.

"It is unclear what steps, if any, federal authorities might take to bring this untenable situation to an end and restore normalcy to this community," Brown wrote. "I must insist on a swift resolution."

In a separate letter to the president Wednesday, Brown said that earlier in the day she had "conveyed the harm that is being done to the citizens of Harney County" to Jerry Abramson, the president's director of intergovernmental affairs.

Document: Gov. Kate Brown letter to President Obama

Brown concluded by thanking Obama "for your timely attention to this matter."

-- Les Zaitz

@leszaitz