He tried to enter a homeless shelter operated by former Mayor Wilson Goode while highly intoxicated and after curfew hours. Two employees at the shelter denied him entry.
John Brock, 32, who turned himself into police custody on Monday afternoon, allegedly responded by going to get a gun, finding those same two employees and opening fire, detectives said.
Station House Men's Shelter employee Edward Barksdale, 43, died from being shot five times. Lamond Barham, 26, an employee at the shelter, was shot once and wounded.
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"Two employees denied him access and police escort him from the premises," said Homicide Unit Capt. James Clark. "Hours later, suspect returns with a gun, walks into the facility, firing multiple times."
Police issued a warrant for Brock's arrest Monday and he surrendered less than four hours later.
Clark said the incident stemmed from a dispute early Saturday morning when Brock, who had resided in the shelter for two and a half months, was denied entry to the shelter due to being drunk and missing curfew.
Police brought Brock to a hospital for a mental health evaluation on Saturday around 1 a.m., Clark said, but he was able to sign himself out on Saturday evening.
He returned at 3:15 a.m. Sunday to the shelter, argued with the two employees about retrieving his belongings and was denied entry.
Around6:13 a.m., Brock returned with a gun Clark described as a small-caliber semi-automatic with plans to shoot those two employees.
"When he returned several hours later he actually asked someone else, 'Are those two employees working?'" Clark said.
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Barksdale and Barham were at a station right inside the front door when Brock returned.
"He enters, turns and attempts to execute both victims," Clark said. Barksdale was shot while seated, while Barham fled and was shot trying to get away down the hallway.
Brock has 10 prior arrests, Clark said and will face murder and attempted murder charges for the shooting.
Court records show Brock was scheduled for trial on Nov. 21 on aggravated assault and attempted murder charges.
He has previously served jail time on drug, assault, and DUI charges and has a last known address on the 500 block of S. 62nd Street, but is currently homeless.
He had a record of past drunk and disorderly behavior at the shelter, Clark said.
"He was a problem resident there. He was drunk a lot of the time and got into fights with some of the other people that stayed there, as well as the staff," Clark said.
Brock is believed to have fled after the shooting on the railroad tracks directly behind the shelter, which are used by SEPTA Regional Rail trains.