On July 26, 1934, at approximately 2:00 a.m., on a clear and moonlit night, the Battleship USS Arizona rams the purse seiner Umatilla and slices it in two off Cape Flattery, killing two fishermen. A Navy Court of Inquiry will fault the captain of the battleship for "culpable inefficiency in the performance of duty" (Record of Court of Inquiry).

The 52-foot Umatilla was owned by Peter Petrich of Dockton on Maury Island. The fishing boat was traveling northwest in the Pacific Ocean approximately two miles off Cape Flattery near the Tatoosh lighthouse ahead of another seiner, the Emblem. The Arizona overtook the Emblem generally from astern at 14 knots. When a collision with the Emblem appeared imminent, the captain of the Arizona ordered the ship's whistle sounded and the Emblem turned to port. The Arizona missed the Emblem by about 50 yards, but rammed the Umatilla in the stern, cutting it in two. Crewmen Lauritz Halsan and John Urosac were killed, and seven crewmen were fished out of the water by the crew of the Emblem.

The Arizona did not stop to render assistance and proceeded enroute to San Diego. Naval Headquarters radioed the Arizona and asked if Captain Macgillivray Milne (1882-1959) was going to investigate. He messaged back, "On account of great delay involved in securing testimony of non-English speaking witnesses and the importance of carrying out present schedule Board of Investigation was not convened on board Arizona" (Record of Court of Inquiry). The Emblem and a Coast Guard tender towed the two pieces of the Umatilla to shore where she was beached.

The Navy immediately held a Court of Inquiry. The survivors sued the Navy for wrongful death and for the loss of the fishing boat. The Court of Inquiry was held aboard the Arizona and aboard her sister ship the Pennsylvania. The Court of Inquiry held that although the Umatilla's lights might not have conformed to regulation, the captain of the Arizona was at fault in the accident.

Subsequent court martial convicted Milne of "Culpable Inefficiency in the Performance of Duty" and sentenced him to a reduction of three numbers in his grade. Under the sentence imposed, Milne would retain his captain's rank, but being reduced three numbers meant that three officers below him would be promoted before he could be considered for a promotion. During testimony, the Umatilla's master Lucas Plancich and crewman Dragutin Beretich, natives of Croatia in what was then Yugoslavia, and Arnold Halsan, a Norwegian immigrant, demonstrated fluency in English

John Urosac left a widow and three small children. His widow Julia settled with the Government for $10,600. Lauritz Halsan's father received $1,200. Two injured crewmen received settlements as well.

In 1936, Captain Milne was appointed Naval Governor of the American Samoa. From 1936 to 1938 he administered what was essentially a coaling station in the South Pacific, but never again would Macgillivray Milne captain a ship of the United States Navy.

The Arizona was sunk by Japanese bombers at Pearl Harbor on December 7, 1941. The Umatilla was repaired and renamed Superior. She was active as late as the 1990s in Alaskan waters.