LAS VEGAS (AP) — Two defendants became the first to plead guilty Thursday to federal charges in an armed confrontation with U.S. officials over grazing rights near cattleman and open-range advocate Cliven Bundy's ranch in Nevada. [...] they acknowledged interfering with the execution of federal court orders by recruiting and organizing armed gunmen to support Bundy and sons Ammon, Ryan, Mel and Dave Bundy in efforts to prevent the roundup of Bundy cattle from the scenic Gold Butte area. Prosecutors characterized DeLemus and Cooper as "mid-level organizers" and leaders of the conspiracy to prevent federal agents and contract cowboys from rounding up Bundy cattle that federal officials said were trespassing on public land. "Federal law enforcement officers must be able to engage in their official duties, including executing federal court orders, without fear of assault or losing their lives," U.S.