>> RELATED: Shooting victim remembered as police seek suspect possibly linked to his death

But some four-and-a-half years later, justice has yet to be served in a case that once seemed close to being solved.

“This one has been by far the most difficult one,” said Atlanta Police Det. Scott DeMeester, a homicide investigator since 2010. “At this point I’ve exhausted all leads.”

Just another Saturday night

The events leading to Cotrona’s death started around 10:30 p.m. on May 25th, 2013.

A married couple, in town for a wedding, had just left neighborhood hangout and bar 97 Estoria in Cabbagetown when they were confronted by a young gunman at the intersection of Kirkwood Avenue and Pearl Street.

As they were being held at gunpoint, one of the victims tried to talk the thief out of it. He responded by firing his gun into the air, leaving behind a shell casing, a potentially crucial piece of evidence.

The suspect jumped into the backseat of a waiting car, either a Dodge Stratus or Intrepid, DeMeester said. The victims said he appeared to be around 16 years old. Five blocks away, at Kirkwood and Stovall Street, the thieves targeted their next victim, a jogger, stealing his cell phone.

>> RELATED: See Atlanta Police Department's list of cold homicde cases

Then it was on to East Atlanta. Cotrona, his roommate, Marcus Peden, and a friend visiting from out of town were just a block away from their destination, Midway Pub, when a Dodge sedan, matching the description of the car seen in the earlier robbery, pulled up alongside them.

They didn’t see the suspect get out of the car. He sneaked up behind them, said Peden, who was plunked on the back of the head with a blunt object.

Sgt. Paula Lyons, Atlanta Police Homicide Unit, passes out flyers offering $25,000 reward for information on the murder of Patrick Cotrona before the start of a a vigil and rally against crime in East Atlanta in this May 2013 file photo. Credit: JOHNNY CRAWFORD / JCRAWFORD@AJC.COM Credit: JOHNNY CRAWFORD / JCRAWFORD@AJC.COM

“Gimme your money!” demanded the suspect, gun in hand. “He kept repeating it, real fast,” Peden said in a 2013 interview with The Atlanta Journal-Constitution.

Cotrona obliged, reaching into his front pocket to retrieve his wallet.

“I don’t know if the guy thought he was going for a gun or something, but that’s when he shot him,” Peden said. Cotrona, hit in the abdomen, slumped to the ground, screaming in pain.

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The assailant seemed unfazed, said Peden, now standing in the gun’s crosshairs. Pretending that he was getting his wallet, Peden reached for his can of mace and sprayed.

“He started screaming then jumped in the car and took off” down May Avenue towards DeKalb County but not before firing an errant shot that grazed Peden’s leg.

A memorial, shown in this AJC file photo, at May Avenue SE and Flat Shoals Avenue SE in East Atlanta marks the intersection where Patrick Cotrona was shot and in May 2013 while walking with friends. Credit: BEN GRAY / BGRAY@AJC.COM Credit: BEN GRAY / BGRAY@AJC.COM

Peden said he never saw the shooter’s face, only a silhouette.

By then Cotrona’s screams had quieted. He was struggling to speak as his breathing became more labored, Peden said. Cotrona was taken to Atlanta Medical Center, where he would be pronounced dead.

‘The random cases are toughest to solve’

At first police investigators had little evidence to work with. DeMeester made the connection to the Kirkwood robberies through ballistics, matching the shell casings from the first robbery to Cotrona’s shooting.

But from there the trail cooled. None of the ATM cards stolen were ever used. Neither were the cell phones. And the .22 pistol the suspect used has never been located.

“There’s nothing we have to distinguish that car from the tens of thousands of Dodge Intrepids or Stratus’ with a sunroof,” DeMeester said. “No physical evidence, no DNA, no fingerprints. All we have is two shell casings.”

A suspect in the murder of Patrick Cotrona, who was shot and killed in May 2013 as he walked home from an East Atlanta pub.

Cotrona’s sister, Kate Cotrona Krumm, has kept in touch with DeMeester. She knows the investigation has hit a dead end, that, as the detective notes, “The random cases are toughest to solve.”

“It’s a sour feeling,” she said. “We keep asking ourselves, ‘What can we do?’ We just feel so inept.”

Cotrona, his sister said, was as much a friend as sibling. They were even roommates for a time after he graduated from Georgia Tech.

“He was so smart,” said Cotrona Krumm, 40. “I loved talking to him. He was a super nerdy guy but had such diverse interests — writing, gaming, knitting, politics.”

As a child growing up in Peachtree City, Patrick was often bullied, said Cotrona Krumm, who was three years older than her brother. She was his protector.

“I still feel like I should’ve been there that night to protect him,” she said.

Cotrona Krumm said she no longer lives in Atlanta. The memories of her brother were everywhere. She moved to Roswell, and a few years ago, she took a new job and moved with her husband to Colorado.

“How could this happen in a place I loved so dearly?” she said about Atlanta. “A place I defended so passionately. I needed a change.”

But distance hasn’t eased the pain.

“We’re always waiting for the other shoe to drop,” Cotrona Krumm said. “Our family needs finality.”

She continues to seek ways to keep the case in the public eye. “I’m thinking about doing a podcast, she said.

DeMeester, the homicide detective, said he remains hopeful Cotrona’s killer will be found.

“The file is still on my desk,” he said. “It hasn’t been shelved. If someone was to call in with information hopefully that’ll be the piece of information that leads to an arrest.”

If you have any information about the shooting of Patrick Cotrona, contact CrimeStoppers at 404-577-8477.

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