Police became aware of 33-year-old Michael Arnold while investigating the August 3 murder of Abigail Gulotta. Gulotta was found dead by a co-worker when she didn't show up at her job at a hair salon.
An autopsy confirmed that the 59-year-old was the victim of homicide.
Investigators learned that Gulotto was seen on August 2 with several members of the Coast Guard. Arnold, who was a Coastguardsman on the Coast Guard Cutter Sherman, matched the description of the person last seen with Gulotta, according to police.
Detectives questioned Arnold, and he denied any involvement in the death and said he had not been off the ship, which was docked in Fairhaven.
On Wednesday, Arnold officially became a person of interest in the case and was brought in to the Belling Police Department for questioning.
Detectives from the Bellingham Police Department and the Coast Guard Investigative Service interviewed Arnold for several hours, but didn't have enough evidence to arrest him at the time, according to police.
Arnold was reported AWOL from the Coast Guard base the next day. Investigators learned Arnold had drained his bank account and may have traveled to a family cabin in Show Low, Arizona.
During their investigation, police were told that Arnold had confessed to the murder and was planning on killing himself. On Saturday, U.S. Marshalls went to the Arizona cabin and found Arnold dead inside of an apparent suicide.