An 18-year-old man serving time for a juvenile conviction has been charged with the September 2011 execution-style slaying of a homeless man at a Seattle bus shelter.

Say Sulin Keodara, of Renton, was charged with first-degree murder and first-degree assault in the fatal shooting of Victor Parker and for allegedly wounding three of Parker's friends Sept. 12, 2011. Keodara, who is serving a one-year sentence in juvenile detention for an unrelated burglary conviction, is being held in lieu of $1 million bail on the new charges.

Keodara, who turned 18 in March, has been charged as an adult in the bus-shelter shooting. He is to be arraigned Aug. 16.

Parker and his friends did not have permanent housing, so they made a habit of sitting in the bus shelter near South McClellan Street and Rainier Avenue South, where they would have a drink and talk into the night, according to other friends.

On the morning of the shooting, Keodara and two of his friends drove up to the bus stop and one of them asked Parker's group whether any of them wanted to buy some "soft," a street term for crack cocaine, prosecutors alleged in charging documents filed in King County Superior Court last week.

Parker may have purchased something from the car's occupants, one of the surviving victims told police.

Fewer than 10 minutes later, Keodara and his friends returned on foot and "demanded money from all of the victims," prosecutors say.

Prosecutors allege Keodara, who has numerous juvenile convictions for unlawful possession of a firearm, began shooting at the victims when one tried to run.

Parker already had been shot once and was on the ground when Keodara "walked up to Mr. Parker and shot him in the head," prosecutors allege in charging documents.

Two other victims, a 43-year-old woman and a 68-year-old man, suffered non-life-threatening injuries, according to police.

The third surviving victim, a 29-year-old man, was seriously injured when he was shot twice in the torso, police said.

Video surveillance obtained from a nearby gas station and drugstore show a car similar to the one described by witnesses stopping at the shelter around 2:31 a.m., prosecutors say.

Images taken from the video were shown to one of the witnesses, who identified the car and the suspect as similar to those involved in the shootings.

A month later, Seattle homicide detectives received a call from an officer with the Wenatchee Police Department who said he had an informant with information about the shooting, according to charging documents.

Prosecutors say the informant told detectives he'd been in a juvenile-facility boot camp with Keodara in the first half of 2011.

On the night of the shooting, the informant received a frantic call from Keodara, who allegedly said he'd shot a man over a drug deal and needed to get out of town, prosecutors say.

Pictures of Keodara were shown to two witnesses, who identified him as the possible shooter, and police obtained a search warrant for his cellphone records, court documents say. The records showed that Keodara had made a call about a quarter-mile from the shooting scene about 10 minutes before Parker was killed, according to the documents.

Christine Clarridge: 206-464-8983 or cclarridge@seattletimes.com

Seattle Times news researcher Gene Balk contributed to this report.