Federal law enforcement officials on Monday sought a peaceful end to the occupation of the headquarters of a U.S. wildlife refuge in Oregon launched over the weekend by a group of self-styled militiamen angry over the imminent imprisonment of two ranchers.

The occupation, which began on Saturday, was the latest skirmish over federal land management in the American West and reflected an anti-government stance held by some Americans.

On Monday morning, a group of about a half-dozen occupiers could be seen outside the facility, with some manning a watchtower and others standing around a vehicle they had used to block the road leading to the building. They chatted quietly among themselves as a large group of media looked on. None was visibly armed.