Tarreece Sampson, 24, was fatally shot near his Alexandria apartment. He is shown with Kaitlin Moylan, his girlfriend of nearly seven years. (Katie Moylan)

Patrick Cuffey and Tarreece Sampson always called each other after Thursday night outings at a Fairfax County hookah bar to ensure each arrived home safely, but in the early hours of May 20, 2016, the routine call would capture Sampson’s killing.

Cuffey testified Wednesday that one moment the popular Fairfax County teacher’s aide and graduate student at George Mason University was telling him he was in front of his apartment complex. The next, chaos.

“Hey, are you good?” Cuffey told a Fairfax County courtroom he heard Sampson ask someone. Then, a single shot rang out. Cuffey said his friend told him he had been shot. That was followed by a gurgling sound, but not another word from Sampson.

Cuffey eventually hung up and called 911, but Sampson, 24, could not be saved. Police found him lying on the ground next to his car in the parking lot of the Cityside apartments in the Alexandria section of Fairfax County. He was suffering from a gunshot would to the chest and was pronounced dead on the scene.

Cuffey’s testimony was key evidence during the preliminary hearing for Charles Edward Benson, one of two D.C. men charged with first-degree murder in Sampson’s killing. Fairfax County police announced Thursday they had arrested a second man, Tre’Sur Hawkins, 19, of Washington, in the case.

Benson was charged in September, but police did not make news of the arrest public until Thursday to protect the integrity of the investigation, they said.

Defense attorney Blake Woloson argued that prosecutors had not tied Benson to the slaying at the Wednesday hearing, but Fairfax County General District Court Judge Michael H. Cantrell ruled there was enough evidence against Benson to forward the case to a grand jury.

It appears Sampson was in the wrong place at the wrong time. Police said Thursday that Sampson did not know Benson or Hawkins and randomly encountered them as they were breaking into cars.

Before Cuffey’s testimony Wednesday, Benson’s brother-in-law, Trayvaughn Johnson, testified he had given Benson and Hawkins a handgun on May 19, 2016. Johnson testified that Benson told him they were going to do “moves,” slang for breaking into cars.

Johnson told the courtroom he later saw Benson and Hawkins during the early hours of May 20, 2016. Johnson testified that Benson told him Hawkins had shot a man. Hawkins was more explicit, forming his hand into the shape of a gun and saying “boom” as he described the shooting, Johnson told the courtroom.

“He said a man tried to stop him from doing what he was doing, so he shot him,” Johnson testified the other suspect told him.

The testimony drew tears from Sampson’s relatives, who sat in the courtroom. They declined to comment after Wednesday’s hearing.

It was not immediately clear if Hawkins has an attorney in the case.

Fairfax County Police Detective Jeremy Hinson testified that several cars had been broken into in the parking lot of the Cityside apartments. A break in the case came in the weeks after the killing when a fingerprint lifted from the door handle of a car matched Benson’s thumbprint.

Benson, who has felony convictions in D.C., was on probation at the time of the killing. He was placed at the Cityside apartments by a GPS monitoring bracelet he was wearing, according to testimony.

Forensic tests also determined the handgun Johnson gave Benson was the weapon that was used to kill Sampson. D.C. police recovered it after Johnson discarded it while fleeing officers in a separate incident.

Benson admitted in an interview that he had been to the Cityside apartments on the night of the killing, Hinson testified, though Benson said he had gone there to buy PCP from a drug dealer, not break into cars.

Sampson was a teacher’s aide at Fort Hunt Elementary School in Fairfax County and was getting a master’s degree in special education, according to an obituary written by his family. Sampson was scheduled to be a special-education teacher in the Fairfax County school system in the 2016-2017 school year. He also mentored students at a local community center.

“T.J.’s spirit will forever live on in the countless lives he touched,” the obituary read.

After Sampson’s death, students at Fort Hunt Elementary planted two trees in his honor. “The healing continues,” the school posted on Twitter, along with photos of students surrounding the trees.