Nearly eight months later, he died at the same hospital from gunshot and stab wounds, his death certificate said. Boston police said he was fatally shot on Falcon Street and was the first homicide victim of 2016.

Investigators have yet to determine whether there is a connection between Perez de la Cruz’s death and the May assault, said Jake Wark, spokesman for Suffolk District Attorney Daniel F. Conley.

“We haven’t ruled out any possibilities at this stage in the investigation, and we continue to urge anyone with information to contact Boston police homicide detectives,” Wark said Friday.

Perez de la Cruz was the third teenager killed in East Boston since September. All three were immigrants. Perez de la Cruz is to be buried in his native Guatemala. Wilson Martinez and Irvin Javier de Paz Castro, both 15, were from El Salvador. No arrests have been made in any of the homicides.

Chelsea Police Chief Brian Kyes called Perez de la Cruz’s death a tragedy.

“This is completely senseless violence,” he said. “Something like this happens in the area and it has ripple effects. There’s always that possibility of retaliation.”

Two Chelsea men, Domingo Tizol, 21, and Brayan Galicia-Barillas, 18, face accusations of armed assault to murder and other charges related to the May attack on Perez de la Cruz, court records show.

Tizol and Galicia-Barillas were arrested after Perez de la Cruz identified them to police as his attackers, the police report said. He said both were in a rival gang and that members of his group had circulated pictures of Galicia-Barillas, the report said.

He said Tizol attended Chelsea High School with him and both men lived near his home. Tizol and Galicia-Barillas are also from Guatemala, court records show.

The attack was captured on surveillance video.

Police said Perez de la Cruz was with a 17-year-old on a bike when they were approached by two men last May. Surveillance video of the assault shows the men hid behind a dumpster before they ran across the street and attacked, according to a report by Chelsea Police Officer Robert Leon Sr.

Perez de la Cruz said Galicia-Barillas “just kept stabbing all over my body,” while Tizol “kept punching me” when he tried to flee, the report said.

Chelsea police and Suffolk County prosecutors believe Tizol is affiliated with a gang, court papers show.

His defense attorney, John Hayes, said Tizol denies being in a gang and has pleaded not guilty to the attack on Perez de la Cruz. He said Tizol “had nothing to do with” the death of Perez de la Cruz.

“He’s not what the police make him out to be,” Hayes said. Galicia-Barillas’s lawyer did not return a message seeking comment.

Tizol and Galicia-Barillas are being held on bail and are incarcerated at the Nashua Street Jail, an official said. They are due back in Suffolk Superior Court next month, court records show.

Perez de la Cruz’s mother declined to comment Friday. The mother of de Paz Castro, who was fatally stabbed Sept. 20 in East Boston, said the boys were friends and the two families are close.

“It’s a pain you never get over,” said Griselda Castro Reyes, de Paz Castro’s mother. “Only God can help me get through this.”

Kyes said he is not aware of any connection between the killings.

At the multifamily home where Perez de la Cruz lived, a neighbor remembered him as a quiet kid who was always smiling.

“God has to do something,” Eli-Lisbet Romen said. “We need peace.”