The very sad shooting of a man on I-5 near 320th on Christmas Day is still being investigated by the Washington State Patrol and Federal Way Police.

The tragic incident involving 11-year veteran State Patrolman S. Michael Cheek and an Olympia man who stripped off his clothing and ran down the 320th exit ramp and into northbound freeway traffic was witnessed by numerous motorists and recorded by State Department of Transportation traffic cameras.

Investigators say that 28-year-old Aaron Larson had exited the car he was riding in with his girlfriend and his younger brother at about 2:30 pm on December 25th and ran back down the offramp and into oncoming, northbound traffic.

Larson had removed his pants and was acting erratically, hitting cars with his belt and according to police transcripts, was grabbing at the doors of stopped cars trying to open them. When Patrolman Cheek arrived, he ordered Larson to stop and the man attacked the trooper. When he could not be subdued when the officer used his Taser, the officer was forced to use his service weapon. The investigation is focusing on whether the Taser was working properly and whether lethal force was necessary.

According to family members, though he had no history of drug use and had quit drinking alcohol, Larson was depressed following the death of his mother and that he had not slept in three days. The victim's father, Jerry Larson said that his son told him that he was having trouble with his girlfriend, that he didn't like living in Olympia and had spoken recently of "having a spiritual event," as well as saying that "someone was trying to kill him."

His sister, Sarah Larson said that her brother was trying to adjust to a new, nighttime truck-driving schedule.

Police transcripts state that a 911 caller who was at the scene in his car that afternoon said, "He was talking about wanting to die."

State Patrol spokesman Cliff Pratt told Komo 4 news that witnesses reported that as soon as Trooper Cheek arrived on the scene, he tried to calm the man, but that Larson immediately charged at him, throwing punches.

After the Officer's Taser failed to stop the man, Larson attempted to choke the Trooper. The situation ended with Trooper Cheek firing his service weapon at Larson, striking him three times.

Larson collapsed on the freeway shoulder and died at the scene.

According to a story in the Seattle Times, a nurse who was a witness to the shooting, Andrea Wolber, suggested that the officer used unnecessary force when he shot Larson. Wolber said she got out of her car and attempted to put a coat over the bleeding man and that she saw the officer fire a third shot after Larson was already on the ground. The Trooper stopped Wolber, saying that Larson was already dead, and then handcuffed the unconscious man. The family plans to sue the Washington State Patrol for using excessive force.

Trooper Cheek, who has never been involved in a fatal shooting while with the department, is currently on paid administrative leave.

According to Police, at least one 911 call, made from the car in which Larson was riding, indicated that Larson had a handgun.

Authorities are investigating where Larson was under the influence of drugs while King County Medical Examiners are still assembling a toxicology report.

A City of Federal Way Press release states that investigators are still reviewing the traffic cam tape and the more than one hundred and fifty 911 calls received during the altercation.

They are requesting that anyone else who may have witnessed the tragic event contact the Puget Sound Crime Stoppers hotline at 1-800-222-TIPS.