HOW TO HELP A scholarship fund has been set up for 14-month-old Louisa Robb. Contribute at any Washington Mutual Bank branch.

Prosecutors said the teen will face an adult charge of murder, which is expected to be filed on Thursday, his 18th birthday.

The teen also was held on a 2002 warrant for failing to appear on charges of car theft and attempting to elude police officers.

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At one point in court, the teen asked reporters: "Why (do) you all have to be in my business?"

The victim, Michael Robb, leaves behind a wife and a 1-year-old daughter. Robb stopped to help someone along West Marginal Way Southwest at about 7:30 p.m. on Sunday when he was killed, friends of the victim said.

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Robb's wife Elsa spoke out Tuesday about her loss.

"Mike was loved by all, a beloved tennis coach, a loving husband and a devoted father," she said.

"He was a good man," said Roger Mark, a tennis teammate. "This was a waste."

SWAT team members along with police aided by dogs and a helicopter searched for someone seen running from the scene after the shooting. At about noon on Monday, officers found the 17-year-old on a barge on the Duwamish River and arrested him.

Police said it appeared to be a random killing, but there were no further details about what happened or what the motive could be.

Detectives are looking for more witnesses in the case.

"It seems random. It's a terrific waste," said Mark. "I hope the person who did this knows what they did, the gravity of what they did."

Robb had been an assistant tennis coach at Newport High School in Bellevue for three years.