The man Anchorage police say is responsible for a deadly mid-March shooting in Jewel Lake appeared in court Saturday, the day after he was apprehended, as charging documents mention a witness to the fatal shots.

Samson Costigan, 39, faces charges of first-degree and second-degree murder as well as evidence tampering in the March 16 death of 28-year-old Jacob Stough. Residents found his body that evening inside a vehicle on the 8900 block of Dewberry Street.

APD spokesperson MJ Thim has previously said that investigators believe Stough's death was "a targeted and drug-related crime."

At a Saturday arraignment in Anchorage Jail Court, Costigan told a judge he was surviving on monthly checks from the Veterans Administration. A judge set his bail at $100,000 Saturday, with GPS-based home monitoring if he is released.

In a March 18 affidavit supporting the charges against Costigan, APD Detective Ross Henikman said police were initially informed just after 7 p.m. on March 16 that Stough had been found dead. His body was at the wheel of a maroon Chevrolet Impala “stopped haphazardly in the middle of Dewberry Street.”

Police found an expended cartridge casing in a driveway “directly across from where Stough was positioned in the vehicle,” as well as “digital evidence” that a Chevrolet Blazer had arrived and left Dewberry immediately before and after the shooting. Henikman said officers had stopped a similar Blazer a week earlier, which was driven by Costigan.

A witness to the shooting told police that he had seen Costigan arrive in the Blazer.

“Costigan exchanged words with Stough who was seated in the driver’s seat of the Impala on Dewberry Street,” Henikman wrote. “Costigan then went into the back seat of the Chevy Blazer and obtained a rifle. Stough was seen leaving the area, backing the Impala down Dewberry Street, when Costigan shot him with the rifle.”

Police hadn’t recovered the rifle used in the shooting by the time the affidavit was filed, Henikman wrote.

Stough's death is Anchorage's fifth homicide of 2018. 

On Friday afternoon, APD again asked for the public's help in locating Costigan; he was believed to be traveling between Anchorage and the Mat-Su Borough evading authorities. 

APD's Investigative Support Unit took Costigan into custody after an alert citizen called in the tip that he was in the Mountain View area. Officer located and apprehended Costigan without incident at a gas station at DeBarr Road and Boniface Parkway.

Costigan is next slated to appear in court Tuesday.

John Thompson contributed information to this story.

Copyright 2018 KTVA. All rights reserved.