The 24-year-old suspect is a documented Aryan Brotherhood gang member with a long rap sheet.

HOUSTON — Police have arrested a suspect in the recent shooting of a mail carrier in west Houston.

Matthew Williams, 24, is charged with aggravated assault against a public servant, aggravated assault with a deadly weapon, felon in possession of a weapon, theft of a motor vehicle, violation of a protective order, and assault of a family member. Police say more charges are possible.

Williams is a documented Aryan Brotherhood gang member with a long rap sheet, according to court documents.

The victim, 30-year-old Adrian Jackson survived the shooting but remains in critical condition.

Jackson was shot around 2 p.m. on Dec. 28 while delivering mail on Cedardale Street near Gessner.

Police say Williams fled the scene and five minutes later, he tried to shoot an elderly man at a nearby Costco gas station on Bunker Hill. Fortunately, his gun didn't go off.

Surveillance video from the Costco scene showed the gunman was a white male with a heavily-tattooed face. He fit the description given by the mail carrier and his neighbors.

Williams later admitted to his brother that he got high and shot a mailman.

They believe the attack on Jackson was random.

Neighbors were baffled by the shooting.

“Kind of surreal,” said one neighbor identifying herself as Kathy. “It just didn’t make any sense.”

Kathy said she was watching TV when she heard four gunshots.

“Maybe a second later, a man is screaming out in pain, ‘Help me!’” recalled Bobby, another neighbor who opted to give his first name only.

Bobby, Kathy, and others looked out and saw Jackson laying by a fire hydrant.

“Someone just got shot right out here,” said another man. “I couldn’t believe it. I called 911 real quick.”

“I lifted his shirt and could only see one hole in his back,” Bobby said.

“I went and put pressure on one of the wounds,” Kathy said.

Another neighbor said the gunman approached one of his workers moments before the shooting.

“He (said) only, ‘Do you got marijuana, or the house is for rent or sale?” recalled the man, who chose not to give his name to KHOU. “That’s it. He left. When he (went) outside, (my workers) hear the shots.”

Neighbors who knew Jackson from his route told KHOU they have no idea why someone would attack him.

“He’d talk to me,” recalled one man. “'How’s it going? Take care. Have a blessed day.'”

“If you had a package, he would offer to bring it into your garage instead of just leaving it on the door for me to carry,” recalled Kelly, who lives nearby. “Just always went the extra mile. Very, very sweet man.”

Houston homicide detectives worked with ATF and the U.S. Postal Inspection Service to track down the shooter.

HPD officials ask anyone with information on the case to call HPD Major Assaults & Family Violence Division at 713-308-8800 or Crime Stoppers at 713-222-TIPS.