An 18-year-old man and his 16-year-old girlfriend were walking on the trail at about 2 p.m. when they were approached by two 18-year-old men, police said. The three men got into an argument over a gang affiliation and the victim was shot through the shoulder, according to court documents. The bullet passed through the man and grazed the 16-year-old girl in her head, police said.

"My friend and his girlfriend were lying on the ground," said Alex Pliler, 18, who said he ran over to the scene after hearing the gunshot from inside his home across the street. "He was shot in his shoulder and then the girl got nicked in the side of the head."

Sheriff's Office spokesman John Urquhart said it "looked like" the bullet passed through the man's shoulder and was lodged somewhere near the girl's ear or the back of her neck.

Both victims were airlifted to Harborview Medical Center in Seattle where the man was listed in serious condition and the girl was listed in stable condition.

Urquhart said two 18-year-old men were arrested in connection with the shooting. One of the men was booked into the King County Jail on suspicion of assault and bail was set at $250,000.

Charges have not yet been filed

A handgun was recovered at the scene.

Investigators said that all three 18-year-old men present at the shooting are known to local police.

Police said they weren't sure what led to the shooting, but Pliler said bad things have happened on the trail before.

"Last year, one of my friends, he was spending the night, he left on the trail and he got jumped by five or six people and had to be hospitalized," Pliler said.

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