Brett Michael Gitchel, the man accused of murdering a woman last seen at a Seattle Mariners game, pleaded not guilty in two separate cases at his arraignment on Monday, April 24.

Seattle police arrested the 46-year-old Gitchel on April 5 for investigation of theft and the murder and disappearance of Leticia Martinez-Cosman, 58, and kidnapping and attempted strangulation of her disabled son.

The last documentation of Martinez-Cosman’s whereabouts prior to her disappearance — a picture of her at the March 31 Mariners game at T-Mobile Park — showed her sitting next to Gitchel.

In addition to Martinez-Cosman’s murder case, King County prosecutors also charged Gitchel for a separate burglary incident on March 28.

Gitchel pleaded not guilty to all charges in both cases, including second-degree murder, first-degree kidnapping, second-degree unlawful possession of a firearm, second-degree arson, first-degree theft and second-degree burglary.

Martinez-Cosman’s brother, Ricardo Martinez reported her missing to the King County Sheriff’s Office on April 2, three days after the Mariners game.

According to documents from the Seattle Police Department, Gitchel attempted to strangle Martinez-Cosman’s disabled son in his vehicle earlier the day Ricardo Martinez declared his sister missing.

Martinez-Cosman’s son followed Gitchel into his vehicle at approximately 2 a.m. on April 2 after Gitchel entered Martinez-Cosman’s home, telling the son he wanted to take him to see his mom in the hospital after an accident.

Gitchel attempted to strangle Martinez-Cosman’s son in the vehicle with an unknown material from behind resulting in a struggle and the son escaping and calling 911, according to documents. Gitchel fled the area in the vehicle.

At 6:49 a.m. on April 2, the Seattle Fire Department responded to a vehicle fire in the 900 block of Golf Drive South in Seattle. Responders extinguished the vehicle, which was identified as Martinez-Cosman’s Honda CRV, and determined that the fire appeared to have been intentionally started with the use of accelerants, the Renton Reporter previously reported.

According to charging documents, cell records of Gitchel’s phone activity used to triangulate the location and position of his phone showed him at Martinez-Cosman’s home in the middle of the night on April 2.

Gitchel’s cell records also show him in the 900 block of Golf Drive South at the time Martinez-Cosman’s vehicle was being set on fire.

Surveillance video showed Gitchel buying a gas can and lighter at a gas station 15 minutes prior to the vehicle fire.

Seattle police apprehended Gitchel on April 5 at a Costco in Shoreline after tying him to the theft of approximately $9,699 worth of diamonds the day earlier from a Costco in Seattle. Shoreline Costco personnel recognized Gitchel from images provided by Seattle police to Costco locations in the area after the April 4 incident.

Approximately 11 days after the Mariners game, a law enforcement search discovered Martinez-Cosman deceased in Renton.

According to documents from the Seattle Police Department, police found Martinez-Cosman’s body near the far west end of South 192nd Street on the north side of the road in Renton. They discovered her face down and partially submerged in a small creek running alongside the road, partially buried with dirt and vegetation moved from an area nearby on top of her.

Seattle Police Department detectives processed the scene and personnel from the King County Medical Examiner’s Office recovered Martinez-Cosman’s body, according to documents.

On April 14, the King County Medical Examiner’s Office ruled Martinez-Cosman’s death a homicide resulting from asphyxiation due to strangulation.

According to documents, police investigation supports the conclusion that Gitchel also used premeditated and intentional lies and deception as with her son to lure Martinez-Cosman into her vehicle and allegedly strangle her, resulting in her death.

“The circumstances necessary to have caused Leticia’s death by strangulation is a manifestation of Brett’s extreme indifference to her life and was the ultimate cause of her death,” states a police document.

The separate burglary case prosecutors have charged Gitchel with involved unlawful access and stealing of items from a residential garden shed on March 28 in Seattle.

He will face a jury trial for both cases scheduled for June 12. although trial dates are often continued. The court set Gitchel’s bail at $5 million.

The Seattle Fire Department responded to a vehicle fire on April 2. Investigation identified the vehicle as Leticia Martinez-Cosman’s. (Seattle Police Department documents)