BURNS, Ore. — The last four armed occupiers of a national wildlife refuge in eastern Oregon said they would turn themselves in Thursday morning after the FBI and other officers surrounded them in a tense standoff. The development came as Cliven Bundy — who led a Nevada standoff with federal officers in 2014 and who is also the father of the jailed leader of the Oregon standoff — was arrested in Portland. The four occupiers yelled at officers to back off and prayed with supporters over an open phone line as the standoff played out on the Internet Wednesday night via a phone line being livestreamed by an acquaintance of occupier David Fry. Fry, 27, of Blanchester, Ohio, sounded increasingly unraveled as he continually yelled, at times hysterically, at what he said was an FBI negotiator.