Last night, police were searching for the alleged gunman, identified as Hector Maldonado, 20, whose last known address was in the 200 block of East Ontario Street.
Reyes was sitting at a table with his girlfriend and other friends at the diner on the 3300 block of Aramingo Avenue after having left an after-hours club, Homicide Sgt. Bob Wilkins said.
While in the diner, Reyes and three other men got into an argument, Wilkins said. Reyes then returned to his table at the other side of the restaurant. One of the men he argued with followed him, then shot Reyes once in the back of the head after 6 a.m., Wilkins said.
Reyes was pronounced dead at the scene at 6:28 a.m., about 20 minutes after being shot.
Customers were "stunned," said Homicide Sgt. Anthony McFadden, adding that most of the diner tables were occupied when the shooting occurred. Some patrons fled into restrooms, he said, while others ran outside.
McFadden said police were interviewing about 12 of the witnesses.
The gunman, meanwhile, "walks right out of the diner," Wilkins said. He fled in a green Chevy Tahoe, which police recovered less than a mile from the diner on the 1800 block of Thayer Street, Wilkins said. He then got away in another vehicle.
Police, who said the two men did not know each other, said they were trying to determine what the two had argued about.
Reyes' slaying followed three separate fatal shootings on Friday and a hail of gunfire that erupted at a playground Thursday afternoon, which left a 17-year-old youth dead. The playground shooting occurred two hours before Mayor Street made a public plea, during a live television address, for teens to put down their guns.
Yesterday, the white stone-and-brick diner, a family business for 50 years, was closed after the shooting, with yellow crime-scene tape blocking off entrances. The diner reopened at 6 p.m.
Jeanette Hoffman, 70, of Port Richmond, said she had heard about the shooting - but was not discouraged from heading there last night.
"I thought it could happen anywhere," Hoffman said. "I come here four to five times a week. You can walk on the street and get somebody to shoot you."
In the parking lot yesterday afternoon, Reyes' girlfriend came by to pick up her car, which had been left there. Her eyes teary, she hugged one of the women with her. Her white shorts were splattered with blood.
"We don't want to talk about it," she said as she got into the driver's seat.
Her father, who identified himself as Pedro Hernandez, was leaving in another car.
"He was a good person, working hard," Hernandez said of Reyes. "He had no problems with nobody. It surprised me he got shot."
Hernandez said Reyes owned the Top Dog's barber shop on B Street, off Allegheny Avenue, on the same block where he lived with Hernandez's daughter and their children. Reyes and his daughter have been together for about five years, he said.
At Top Dog's yesterday, in a neighborhood of rowhouses with small Hispanic grocery stores, handwritten signs were posted in English and Spanish saying the business was temporarily closed. Reyes also owned the Ambicion Cafe nearby.
Reyes leaves behind eight children, ranging from 1 year old to 13 years old, family members said. They did not say how many of the children were from his current girlfriend or his former wife.
Police said yesterday that they were still searching for suspects and motives in the Thursday playground shooting and in three slayings that occurred on Friday.
Early Friday, Shakeem Perry, 21, was shot inside his residence in the 5000 block of Jackson Street following a home invasion.
About 6:30 p.m., Donovan O'Conner Malcolm, 47, was shot in the chest near 52d and Arch Streets in West Philadelphia. He was taken to the Hospital of the University of Pennsylvania, where he died about a half-hour later.
Then about 8 p.m., a man believed to be in his early 20s was shot in the chest in Frankford near Leiper and Overington Streets. He was taken to Frankford Hospital-Torresdale Campus, where he was declared dead on arrival. His name was withheld yesterday pending notification of next of kin.
Contact staff writer Julie Shaw at 215-854-2917 or firstname.lastname@example.org.
Inquirer staff writer Jan Hefler contributed to this article.