Adrian Bueno was arrested by the San Luis, Police Department in Arizona after he attempted to gain access into the United States, according to a field report.
Bueno, 29, is connected to the January 31 shooting of Victor Ramos.
Local investigators identified Bueno as the registered driver of a black 2007 Infiniti G35 and Francisco Rudy Gallardo as the shooter.
Gallardo, 41, remains at large in the killing of 28-year-old Ramos.
Sunnyside Police said Ramos was found with a gunshot wound in his chest outside his residence on the 1200 block of Roosevelt Court around 4:15 p.m. on Sunday, January 31.
Ramos was taken to Astria Sunnyside Hospital where he later died from his wound.
Anyone with information about the case is asked to call the Sunnyside Police Department at 509-836-6200 and cite case number 21s00931 or Yakima Crime Stoppers at 800-248-9980.
Tips can also be submitted online at http://www.crimestoppersyakco.org